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alanjgreen

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Everything posted by alanjgreen

  1. Here are last nights results - three successes and one fail. Note that AT2020ftl has brightened to mag 14.4.
  2. Date: Saturday 11th April 2205-2350hrs Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (f2 x38), Panoptic 35mm (f3 x60), Panoptic 27mm (f4 x77), DeLite 18.2mm (f5.8 x115). Moon: 0% Background Last Nights Results. I managed to get a couple of hours outside last night. The first hour had decent conditions (M61 showed some lovely spiral arms as I warmed up) but during the second hour conditions steadily deteriorated until I gave up... 1. NGC4277/SN AT2020ftl = SUCCESS I was able to see the bright SN in all my Night Vision eyepiece combinations (x38 thru x115) but it was only separated from the core in the 27mm and 18.2mm eyepieces 2. NGC4568 (Siamese Twins)/SN2020fqv = SUCCESS I was able to see the bright SN in all my Night Vision eyepiece combinations (x38 thru x115), probably the best view was with the 27mm eyepiece. Although it was clearly seen at x38 with the 55mm eyepiece. 3. NGC5157/SN2020ees = FAIL I was not able to see anything other than the core in this galaxy. 4. NGC5635/SN2020fcw = SUCCESS With the 18.2mm DeLite (x115), I was able to see two dots in the galaxy disk. At first they appeared side-by-side (9 o'clock to 3 o'clock) but with time they seemed more 8 o'clock to 2 o'clock slightly angled. 5. NGC5258/SN2020dko = not enough time! I had found the galaxy and orientated myself to my pre-match sketch but the two galaxies were hardly visible as that part of the sky had not rotated around to my drop-down side and the shed wall was taking away most of the light plus the conditions were deteriorating as well. I ran back though the previous SN one more time, but they were all much harder as the sky had gone. Still, more clear nights next week so look forward to that. Alan
  3. With clear nights forecast next week and the moon getting later to rise 😀, I have done some SN research this morning to id some targets for next week... Here are some scans of my research notes and star charts for use next week... I will be targeting the following new SN: AT2020ftl, NGC4277, Mag 14.9 SN2020dko, NGC5258, Mag 16.6 AT2020enm, IC1222, Mag 16.7 SN2020fqv, NGC4568 (Siamese Twins), Mag 15.3 SN2020fcw, NGC5635, Mag 16.1 SN2020ees, NGC5157, Mag 16.5 Happy hunting... Alan
  4. Equipment Used: Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepiece: Plossl 55mm (f2 x38). Background. In spring 2019 I created a Sky Safari observing list of 214 highest brightness galaxies in the night sky above. I have observed 134 of the 214 (the others have not been well placed over my garden when I have been outside). In my first pass through these 134 galaxies, they were graded 0-3 (where 3 means "clear spiral arms" and 0 means "nothing to see here!") I have now completed a second pass through the grade 2 and grade 3 galaxies. This has resulted in some movement between bands based on my now greater experience and having a better idea of what I expect to see. My latest graded lists contain 38 grade 3 galaxies and 30 grade 2 galaxies (when combined this gives a list of the best galaxies to view when using military night vision technology combined with a low power eyepiece (using the TeleVue PVS-14 adapter). [Note that lower power eyepieces give the best spiral arm results as they “increase the effective focal ratio” of the telescope/night vision system which really helps increase the detail seen at the eyepiece.] As we are still in galaxy season 2020, now seemed a good time to re-publish my findings so others have the opportunity to observe some of these fantastic galaxies before they become “unavailable” for another 10 months… Grade 3 galaxies (the best of the best). M51 M61 M64 M65 M66 M81 M90 M91 M94 M95 M96 M99 M100 M101 M106 M109 NGC891 NGC2403 NGC2903 NGC3184 NGC3628 NGC3631 NGC3726 NGC3893 NGC3953 NGC4051 NGC4216 NGC4274 NGC4449 NGC4559 NGC4565 NGC4618 NGC4725 NGC5248 NGC5371 NGC5746 NGC5907 NGC6946 Grade 2 galaxies (good but the arms are not quite there…) M82 M88 M98 M104 NGC2537 NGC2768 NGC3294 NGC3344 NGC3373 NGC3596 NGC3646 NGC3675 NGC3718 NGC3729 NGC3813 NGC3938 NGC4013 NGC4214 NGC4293 NGC4389 NGC4490 NGC4517 NGC4535 NGC4625 NGC4762 NGC5005 NGC5364 NGC5383 NGC5775 NGC6015 Hopefully someone will find this useful information, next time they plan a galaxy observing session... Note that my dobsonian uses an Astrodevices Nexus unit which I control using Sky Safari. Here are my exported observing lists (which you can import into your Sky Safari app should you wish to do so?) Grade 3 Galaxies.skylist Grade 2 Galaxies.skylist 1. email them to your phone/ipad, 2. read the email on your mobile device and after clicking on the attachment, you should be offered the chance to “send to Sky Safari” by your email app… 3.Sky Safari will open and give a message “Observing List Created”. Clear Skies, Alan
  5. Date: Friday 20th March 2020. 2300-0305hrs. Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Panoptic 27mm (f4 x77), DeLite 18.2mm (f5.8 x115). Introduction. Unbelievably, I just completed my third straight night outside observing Hickson Galaxy Groups and Supernovae. After months of thin gruel, I am beside myself although a little tired it must be said! Conditions last night were the best so far and my results improved as a result... Hicksons (3 new to me). I spent yesterday making an updated Sky Safari observing list. My aim was to edit the “full Hickson observing list”, remove all those that I have observed to produce a “To Do Hickson” observing list. I will add the steps taken to do this at the bottom of this report in case anyone is wondering how this is done? Hickson 54 – Sky Safari lists this as having one member IC700. I centred the target in the 27mm Eyepiece (with Night Vision device attached) and immediately saw a long thin edge-on galaxy patch. This thin line is in-fact made of 4 galaxies but I was unable to split the line on this occasion. Hickson 50 – (“The faintest Hickson” according to what I have read while doing research the last couple of days). It is also not present in Sky Safari when you search for “Hickson”! I used galaxy “PGC 2485269” to locate the correct area of sky to search for Hickson 50. As I look into the eyepiece a tiny double patch caught my eye straight away! With time, I got glimpses of a third patch to the right of the first two. I knew that I was looking for a pentagon shape of galaxies and there seemed to be a general faint glow in the area where all these galaxies are hiding. I waited but none of the others came into view.😀 Hickson 62 – Sky Safari has a major fail for several of the Hickson catalogue in that it shows them as having too many members (20+) in some cases. I nudged around the oversized Sky Safari search area and came upon a patch of three tiny galaxies, checking my Ipad Sky Safari showed NGC4761, NGC4759, NGC4764 and some research this morning confirms these findings.😀 I came upon a great website detailing the Hickson galaxy group members: https://translate.google.com/translate?hl=en&sl=de&u=http://www.deepsky-visuell.de/Projekte/HCG34_66.htm&prev=search This information is really useful and I thank the author for publishing this data for me to find!😀 Supernovae (6 from 7 attempted). Okay, onto the main diet for the evening… IC738/SN2020vg - SUCCESS. Repeating my observation from the previous night, the galaxy was once again tough to find. Once you have it then the elongated core can be seen within with the 18.2mm eyepiece. Images don't show a split so I am marking this one as a success. PGC 041887/SN2020cdm – SUCCESS. I located the galaxy successfully in the 35mm, 27mm and 18.2mm eyepieces. It is located to the right of a small, mid-brightness “Xmas tree” star formation. A small patch is easily seen. Then it’s a case of letting the patch drift across the fov many times and watch for activity within using averted vision. With the 18.2mm eyepiece I was able to get 3 of 4 glimpses of a dot within the galaxy patch. NGC5371/SN2020bio – FAIL. I spent a long time on this large side-on galaxy but there was no sign of the Supernova in any eyepiece. I even tried an Ethos 10mm (conventional eyeball viewing) for greater magnification but the SN was not seen. I now doubt my observation from 18 March too. UGC9945/SN2019zhs – SUCCESS. With the 27mm eyepiece I quickly found the galaxy and could see the core within. Using the 18.2mm eyepiece I got occasional glimpses of two dots within the galaxy disk. PGC056547/SN2020dxa – SUCCESS. This is an easy target and it was nice after the work I had to put in on some of the previous ones! With the 18.2mm two dots within a dust patch are easily seen. UGC10661/SN2020awa – SUCCESS. The galaxy sits within a small triangle of stars (one corner of the triangle has 2 stars). With the 18.2mm eyepiece I could make out a dot within. PGC062161/SN2020duu – SUCCESS. This is another fairly easy one. It took a bit of time to find the edge-on galaxy. But once you have it there is a clear dot on the leading edge as it drifts across the fov. Conclusions. After having two nights of not much sleep, I needed to pace myself last night. I delayed going out until 2300hrs so as to be able to stay out later without getting tired too soon. I am pleased to say that it was also warmer last night than the previous two nights (when I had to wipe of ice from the scope before packing away for the night). Perseverance is key with supernovae, you need to try them a few times to get the “lay of the land”. It’s amazing how you become familiar with the star patterns in the fov of the supernova’s parent galaxy. It’s like visiting an old friend by the third night. But it takes patience and concentration to get the faintest targets to pop into view and I was pretty tired by the time I packed up just after 3am. Clear Skies, Alan How to edit a Sky Safari observing list using Ipad & PC. Search for “Hickson” in Sky Safari Scroll to bottom of list and choose “create observing list” Use search to open the new observing list and scroll down to the bottom and choose “email observing list” On your PC, save the email attachment to desktop and add “.txt” to the end of the filename Edit the file with Notepad. Remove unwanted objects and save the file Remove “.txt” from the filename and email the file back to your Ipad On the Ipad, choose the email attachment and then choose “Sky Safari” when it asks what app you want to open the attachment with...
  6. Date: Wednesday 18th March 2020. 2200-0240am Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (f2 x38), Panoptic 35mm (f3 x60), Panoptic 27mm (f4 x77), DeLite 18.2mm (f5.8 x115). Introduction. This is turning out to be a poor year for observing. It’s been another two weeks of cloud or full moon blocking me from getting outside for the last 17 nights! The good news is that a clear spell has landed over the UK and new moon is approaching... Last night I was out for four hours and had drawn up an observing plan of 12 current supernovae and also had my Hickson galaxy group observing list to continue working on. Supernovae (2 from 4). Unfortunately conditions were not perfect and visibility was not good to the low down south where a number of supernovae targets are located. But I attempted the targets that were well placed and available to me… NGC 3395/SN ASASSN-19aea – With the 18.2mm DeLite it was easy to find the two interacting galaxies. One galaxy was clearly larger and had a faint curved appearance where the arms were partially visible. There are 3 faint stars close-by for orientation and the galaxy next to the single star is the one with the SN. This larger galaxy definitely had a bright core which was elongated but I could not split the SN from the core. I tried the 27mm Panoptic (for increased brightness with the night vision device) and the field stars were easier to see but I could still not split the core & SN. FAIL. NGC 5371/SN2020bio – My first attempt before midnight was a fail. The galaxy was easily seen in the 27mm eyepiece and its large too. I matched field stars to my view for orientation but there was no sign of the SN. I revisited this galaxy after 1am and this time the view was improved and I did get glimpses of a faint dot coming and going (mainly going) in the location of the SN! SUCCESS. 😀 PGC 056547/SN2020dxa – This one was easy to find and see! With the 27mm eyepiece you can see two dots (clearly separated) within the tiny galaxy patch. There is a double star above pointing the way to the galaxy and (unfortunately) there is a bright field star LHS causing reflections in the fov! SUCCESS. 😀 UGC 10661/SN2020awa – This galaxy is hard to find. It sits in a small field star triangle (one corner of the triangle has two stars, the other corners are single stars). I tried both 18.2mm and 27mm eyepieces but I could not split the SN from the galaxy core. FAIL. Hicksons (7 new to me). Hickson 68 – With the 55mm eyepiece, I could easily see three galaxies straight off (two bright galaxies in a pair with the third separate below). Looking around I could also find two tiny smudges to the RHS (each separate). Hickson 70 – With the 27mm eyepiece, I could see three galaxies that appeared evenly spaced in a line. There was a close pair of galaxies just below them (uneven brightness). Then one additional faint fuzzy off to the RHS. 6 galaxies. Hickson 71 – 27mm eyepiece. Three stars close together are see next to two galaxies that a gap RHS to a tiny galaxy smudge. The last galaxy is in-between (in the gap) and very faint indeed (cannot be held in direct vision). Hickson 69 – 27mm eyepiece. Three galaxies in a triangle formation are easily seen. Wow, there are so many galaxies in and around the fov that I feel overwhelmed by the sheer number and have to keep checking Sky Safari to see if I have the right ones targeted!😀 Hickson 66 – 27mm eyepiece. 3 of 4 seen. Three tiny galaxies seen in a tiny patch in a 2+1 formation. Hickson 45 – 27mm eyepiece. A pair of tiny galaxies are found in-between 2 field stars. There is a possible third galaxy faintly seen underneath. Hickson 49 – On March 1st I failed to find this object (due to the moon) but tonight I found it. 😀There is a very tiny patch of faint fuzzies! There seems to be several very close together. I could see two cores intermittently from within the tiny patch. Epilogue. Cloud started rolling over in patches and I was having to pick my spots (of clear sky) which was painful. With more clear night forecast, I decided to go to bed instead. Clear Skies, Alan
  7. Date: Sunday 1st March 2020. (2240-0220am) Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (f2 x38), Panoptic 35mm (f3 x60), Panoptic 27mm (f4 x77), DeLite 18.2mm (f5.8 x115). Filters: Baader 610nm Red Filter Moon: 39% Introduction. Wow, it’s already March and I’ve just completed my first real session of any note in 2020! The weather in the UK has been pants since Christmas. I have managed a couple of two hour dashes between the clouds but that is not enough time to really get into a session and do any real observing on any more than a few objects so I have mainly been observing the more famous and brightest night sky objects. Galaxy season is here! Yay, my favourite observing season is here. With all this down time, I at least had an observing plan to follow when the opportunity finally came. I had created observing lists in Sky Safari of the Hickson and ARP catalogs. Making a start on the Hickson catalog with Night Vision. There was a 39% moon in the West so I had to deploy a Baader 610nm Red filter to the front of my Paracorr2 to remove the unwanted moonlight from my view. On the first object, I tested out all the eyepieces listed above to see which produced the “best” view. There is a trade-off with night vision devices of image brightness and image magnification and I wanted to identify the best eyepiece option up-front as I intended to attach my eyepiece heater tape and then stick with the one eyepiece for the session. I settled on the Panoptic 35mm as my chosen eyepiece as it was giving decent image brightness resulting in more galaxy halo and the magnification (x60) was enough to provide something to see from these tiny objects. Hickson 37 – I could see three galaxies in a row close to two field stars. One galaxy was a longer edge-on and one had a bright core with faint halo. I found the fourth group member nearby just the other side of a field star although this one was a challenge to hold in vision for long. The final galaxy was glimpses occasionally with a real effort and concentration needed. Hickson 44 – Two small bright galaxies were immediately obvious, I soon located a third slightly separated galaxy of mid-brightness out in front. The final galaxy was the faintest of the four and was sited at 90 degrees to the side. All four galaxies were easily seen in direct vision. Hickson 46 – This group was hard to locate initially then I spotted two cores appearing close together in the field of view. After letting my eye settle in the other two galaxies appeared one on either side of the first two. Hickson 47 – Two cores were immediately obvious in the fov then one more emerged lower (near a field star). I did get glimpses of the fourth member which was in close to the third galaxy staggered to one side. Hickson 38 – Another group that was tough to find. Found just above left of two bright stars. Time reveals three galaxies in a triangle formation. The lower galaxy was the easiest with a nice halo. The upper two were smaller and fainter. Hickson 36 – The toughest so far! I found a possible very faint patch just below 6 stars. It looked like two groups of three galaxies but looking at images this morning then this looks incorrect so this goes down as a fail. Hickson 35 – Found inside a triangle of field stars. Three galaxies easily seen in a flat triangle formation. There was a possible fourth galaxy glimpsed to the left which was fainter. Hickson 41 – Two galaxies easily seen (one has a core and halo). The third was tough and appeared just under the fainter of the first two. No sign of the fourth member. Hickson 60 – A small patch is easily seen in the fov. One core dot is seen within the patch off–centre. Hickson 56 – This tiny group is located next to two much larger and brighter galaxies (NGC 3718, 3729) that overpower your vision as you reach the eyepiece. Once I was settled on my actual target then I saw two tiny bright galaxies first. Then the third was seen slightly separated to the RHS. Then one appeared LHS fainter giving a 3+1 appearance to the group. Hickson 55 – The small patch was quickly located in the fov. I could see two dot cores appearing on and off within the patch but not much more. Hickson 49 – not found. Hickson 61 (Box Galaxies) – A nice sight. Three bright galaxies make up three corners of the “box”. A fainter larger galaxy sits at the other corner. The two brightest galaxies were at the top side. The bright lower galaxy has a halo. Hickson 51 – Five galaxies are easily seen in the fov, appearing as 3+2. The galaxies appeared well spaced but were small. Hickson 57 (Copeland Septet) – A very nice galaxy group! I could see 7 galaxies appearing as 3+3+1 formation. All easily seen. Hickson 53 – I saw three galaxies in the fov in a 1+2 formation. The fourth member (off to the right) was not seen. Hickson 52 – Two galaxies were easily seen. Another galaxy is glimpsed intermittently near to the second galaxy with time at the eyepiece. Hickson 59 – 3 of 5 galaxies seen. Two are bright and easily seen. The third appeared at a right angle to the first two with the gain turned up. Hickson 58 – Four galaxies are easily seen in a 2+2 formation. The fifth needed further exploration but clouds starting passing and my session was cut off in its prime! Epilogue I make that 18 Hicksons attempted last night which seems like a good start and I am pleased with that. Most of the observations were taken with the Moon up so it will be interesting to try them again on a new moon to see if more can be seen… It was great to be back outside after nearly two months of slim pickings! Clear Skies, Alan Some Technical Background (Voluntary reading!). This section is added for anyone wondering why I was only using x60 magnification with my setup and maybe “more would be seen with greater magnification?”. While that would be true with traditional observing, night vision is best used with eyepieces with large exit pupils as the more light you get into the device then the more light it has to work with. Longer focal length eyepieces (greater than 27mm) also have a side-effect of increasing the effective focal ratio of your telescope system (as far as the attached night vision device is concerned) and as the NVD works at f1.2 then the closer we can get to that speed the better the results will be. So the facts are that the 55mm Plossl with always show the brightest view possible with the most galaxy details possible seen within that view. But when tiny objects are tightly packed then you may need more magnification to separate them (this is usually true for supernovae hunting for example). But as you increase magnification and decrease the exit pupil/effective focal ratio of the system then galaxy detail will be lost from the view. I only ever view galaxies where I hope to see the spiral arms with the 55mm Plossl as I want maximum brightness and fastest effective focal ratio.
  8. Report of my Virgo supernova hunting from 0200-0400 on morning of Jan 19th 2020. Equipment: 20" dobsonian f3.6. Televue Delite 18.2mm & PVS14 night vision device. Outcome: 4 supernovae observed successfully. NGC4441 & SN2019yvq - Supernova obvious and immediately seen. Held in direct vision close in to the core. M100 & SN2020oi - Bright supernova outshines the core close in and is easily split from the core too. Decent amount of galaxy shape and faint arm structure fills the fov. NGC4636 & SN2020ue - This is a little trickier as you need to determine which "star" is the supernova. But the supernova "star" is the brightest of the patch of five it sits within. Use the two brightest stars just outside the core to orientate yourself (images were upside down for me). The faint star closest to the core is the hardest to spot and was intermittent for me. The next 2 stars from the core are the most obvious (and the SN is one of these 2). The final 2 stars in the group of five take some staring to get to see but once you locate them you can continue to see them. NGC4666 & SN2019yvr - The toughest of the bunch! The galaxy is huge and clear in the fov. There is a group of 3 tight stars above (for orientation purposes) and the SN is located underneath away from the flat disk. I had to wait a few seconds before I got a brief glimpse of the SN as the galaxy drifted across the view. I glimpses it 4 more times during my time letting it drift across the fov. A toughie for sure. http://www.rochesterastronomy.org/supernova.html?#2019yvr Hope this helps others find them, Alan
  9. I was out last night for the first time in 2020! My main focus had been the Orion area but by 0100am it had moved too far west of the shed, so I had a great time with the Eskimo nebula (that’s another story) before trying to centre the three current supernovae in Virgo. The only galaxy of the three that I could reach (with the dob from the shed) was M100 and I am pleased to report that this is a bright (mag greater than 13.2) type 1c. As soon as you see M100, the SN is obvious and much brighter than the core it sits beside. I was using the 20” and recorded the following results using a night vision device connected to various eyepieces: - 18.2mm Delite (x111 magnification), easy split from core, no galaxy extension or arms seen (this is a large physical galaxy when seen in all its glory). - 27mm Panoptic (x75), split ok, no arms seen but galaxy is now a larger patch. - 35mm Panoptic (x59), SN is very close to the core but easy to see as it’s so much brighter. I now see the full scale of M100 but the arms remain just beyond reach. I encourage everyone to give this a try as it is bright. Clear skies, Alan
  10. Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: DeLite 18.2mm (f5.8 x115). I was out supernovae hunting last night with three SN targets planned 1= NGC109/SN2019upw 2= UGC11860/SN2019tua 3= UGC11979/SN2019tgm I am happy to report that I observed 2 out of 3. Here are some notes to help others. NGC109 / SN2019upw This one is fairly straightforward as there are few field stars in the area. Once you find the three brighter stars in a triangle then the galaxy is easily seen in the centre. There are 4 faint stars on one side of the galaxy and one on the other. The SN is separate from the core. As I was only using x115 magnification then the split was not straightforward and time was needed to wait and observe for the split to come and go! UGC11860/SN2019tua This galaxy was really well placed at the zenith at around 1830 last night. The galaxy was not seen but the SN is there. It takes time to find the right spot but there is a field star "3D cube" just above, once you find the cube then you can find the SN. (See stars marked A,B,C,D on my diagram, the Supernova is X). UGC11979/SN2019tgm This is the toughest, there are so many field stars that it is hard to find what to match to the internet images. Anyway, it turned out that I was looking in the wrong place but the stars I drew do match the images so I was just a small way off. Look carefully at my sketch and there are two rows of field stars (the 3+2 and the 3, the middle star of the lower 3 is a double), if you can find these two rows of stars at the eyepiece then the SN is in-between these rows as shown by the blue box (added this morning). I was looking further up in a tight cluster of stars where the tiny galaxy appeared to be (my mistake!). Happy hunting! Alan
  11. NV is made for infra red part of the spectrum and Ha (hydrogen alpha) is red. Therefore any source in the night sky that is strong in Ha will appear easily with night vision. The narrowband Ha filter allows me to filter everything else away and then nebula just pop out into view. What I really like is seeing the jet black hydrogen sections which really stand out much better than with no NV. I did an experiment to observe M33 reported here, where you can see my sketch showing how the areas on new star birth really pop out with the filter. For general galaxy viewing, no filter or a UHC filter works well (to get rid of the moon light for example). It is the tiny galaxies where all the light from the galaxy is concentrated in a small location that are easiest to see! Hickson groups are easy for instance. The larger galaxies where the red Ha light is less concentrated are not so good but with the right magnification (and fast focal ratio) arms can be readily observed in many galaxies ( I have seen arms in 68 galaxies so far). Leo and Virgo are superb with NV, tiny galaxy patches everywhere. With the 20”, I can now observe PGC and UGC galaxies easily. Supernovas to mag 17 are now achievable too. Night Vision is not a one trick pony but you need a scope with long focal length, Dob or SCT to get decent magnification from a 55mm plossl. You need the 55mm plossl to get the effective focal ratio of your system doubled and get more light (exit pupil) into the NV unit. Alan
  12. Dates: 28th & 29th November 2019. Scopes: 20” f3.6 Lukehurst Dob & Borg 107FL f5.6 (focal length 600mm). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (Dob f2 x38, Borg f2.6 x11). Filters: Chroma 5nm Ha filter. Introduction. Last time outside was the 8th November and I had a great night with the Borg 107FL and Night Vision identifying many new “areas of interest”. See my report and sketches here: But then we have had three weeks of clouds! Anyway, last weekend we got three clear(ish) nights outside so I decided to use the Borg 107FL as a spotting scope to identify further areas to then check out with the Big Dob. It seems that it is easy to look straight through faint nebula and not see the bigger picture with the greater magnification proving a disadvantage with the dobsonian. This report will cover a mix of two sessions (Night one – Borg 107FL) and (Night Two – 20” dobsonian). I will detail my wide field observations and sketch and then follow up with the detailed greater magnification/aperture view of the exact same area accompanied by a photo from Sky Safari with locations marked. Area of interest 1 – Heart & Soul nebula region. Starting with my wide field observations, here is a sketch I made of this area of the sky. The big thing I found was a rectangular structure that is attached to the side of the Heart nebula. It had some brighter areas within it and a smaller parallel line inside it. There was an obvious “loop” coming from the “mole head” part of the Heart and beyond the loop I saw a small patch and a longer snake patch too. I have marked some of the smaller Sharpless (sh) that I saw on the sketch as well. After quite a long time examining the Heart, I slewed to the Soul (foetus) next door, where some nice intricate interior detail and brighter mouth and chin areas were observed together with a couple of small Sharpless just of the sides were also noted. Now, onto the Dob observations from the following night. Here is a Sky Safari view… GSC 4051-1604 – large faintish patch fills fov. Stars have cleared black areas inside. Double star in a black patch stands out. TYC 4054-1657-1 - marks the right angled corner of faint box extension to heart nebula. HD 15022 – Triangular shaped patch fills fov. Some small black areas inside. GSC 4046-0016 – a “line” section. Two brighter patches stand-out. TYC 4050-2042-1 – return section of “loop”. Exiting & returning to the “mole head”. TYC 4056-1055-1 – Long curving corner section of faint nebula lane coming from the Heart. TYC 4051-2885-1 – Junction of two curved loops (curved X shape), brighter central area with black patch & stars inside. TYC 4059-0328-1 – very faint large section of reflection neb. Plenty of black helps the nebula to stand out. GSC 4058-0834 – “house” shaped star cluster set in a large nebula patch. TYC 4052-1055-1 – small nebula patch (part of a long thick curvy lane that winds along here). SAO 012401 – very tiny, bright nebula patch. HD 20798 – small circular patch next to a star (the last in a line of stars). Black circular area too. TYC 4049-0064-1 – double lane of nebula. One side brighter with some brighter patches too. Area of interest 2 – Flaming Star region. It was time to revisit the Flaming star region. I familiarized myself with a look at my sketch from last time out then started to note and sketch further nebula details seen at the eyepiece. I could see a sketch what looked like loops of nebula coming from the main bright blobs (sketched as dashed lines). There was a clear right angled corner piece above IC417. I then hit the multi-patched area of sh2-233/235 which looked great. On the other side there was a sweeping curved section that ended in a double patch (maybe sh2-227). I could see a small bright blob below that (guessed as NGC1778 but may be something else sh2-228?). Finally, I noted a small patch hanging off the side of the Flaming star itself. Here is my sketch from 28th November. Now, onto my 20” dob observations from the following night… TYC 2393-1581-1 – oblong patch to LHS of tail of Flaming star. HD 243596 – patch between IC410 & Spider. HD 36834 – thick lane of nebula brighter section connects to HD35345. TYC2415-0413-1 – large patch connected to HD35345. HD 36212 – large nebula patch with many stars. SAO 058274 – large nebula patch under the pinwheel cluster. More work needed here... Area of interest 3 – Fox Fur & Rosette region. Next, the Fox Fur & Rosette, which is proving to be a great area to explore with a small wide field scope. The Fox Fur is rising rapidly up the list of “great nebulas of the night sky”! Once again, I started by checking my sketch from last time out and then worked to see and sketch further details… Here is what I ended with… It’s really hard to find a decent image of this area wide field. Everyone seems obsessed capturing the tiny Cone and misses out on the vast lush areas greatness! Search for “Fox Fur Nebula Rosette” and you can find some – it’s well worth it. This time I noted some of the black detail inside the thick “comma” shape and also a smaller detached patch above. I cannot reach this region from my shed so there is no dob confirmation text. Area of interest 4 – IC434 & Horsehead region. Onto the expansive region that contains IC434 and the horsehead. Last time out I noted a long extension to the left hand side and down parallel to IC434. This time I was lucky enough to see even more. IC434 was a complete rectangle of nebula surrounding Sigma Orionis in its centre. With more time I began to notice a separate nebula lane running up the left side of this. It was fainter and ended with a curvy section around Alnilam at the top. The bottom end was right angled as shown below in my sketch… I cannot reach this region from my shed so there is no dob confirmation text. Finish with the search for some Comets. I was out again on the 30th November where I managed a couple of hours observing before fog descended. The highlight was that I bagged four comets as follows: Equipment: 20” dob, 27mm Panoptic (x77 magnification), PVS-14 Night Vision. C/260P McNaught – A small fuzzy blob next to a star. No core to speak of. C/114P Wiseman-Skiff – (found WEST of where Sky Safari says it is so beware!) It appeared brighter than C/260P. A small fuzzy patch with wide brighter core (but not a bright “dot” core). C/2018 N2 (ASSASN) – Easy. Bright dot core and halo surrounds. Next to 2 stars LHS. C/2017 T2 (PANSTARRS) – Very Easy. Bright dot core and dust halo. Small tail heads NW. Epilogue The above approach proved a success, identifying potential areas for detailed searching with the dob in advance really helped me to focus where I looked with the dob and helped me to linger longer at a location waiting for nebula to pop out at me. I will be relocating the dob to the back of the shed for the next new moon so Orion and the Rosette can be reached. Then I can firm up some more exact locations thanks to the push-to connection to Sky Safari that the dob has (via a Nexus wifi unit). Clear Skies, Alan
  13. Just bagged 10 minutes between the clouds and got to see the Mercury shadow transit! Its so long since I used the Lunt that I took a few seconds to get back into the groove of tuning the double stack and letting some air into the tuner as it was flat. Not much else on the disc - 3 x sets of proms, 3 tiny filaments, saw one small bright flux patch briefly. But the Mercury shadow was nice and clear and a decent sized patch too. Just got back inside before it started spotting with rain! Fingers crossed for another clear patch later ... Ala
  14. Just bagged 10 minutes between the clouds and got to see the Mercury shadow transit! Its so long since I used the Lunt that I took a few seconds to get back into the groove of tuning the double stack and letting some air into the tuner as it was flat. Not much else on the disc - 3 x sets of proms, 3 tiny filaments, saw one small bright flux patch briefly. But the Mercury shadow was nice and clear and a decent sized patch too. Just got back inside before it started spotting with rain! Fingers crossed for another clear patch later ... Alan
  15. Date: Friday 8th November 2019. 0300-0600am Scope: Borg 107FL f5.6 (focal length 600mm). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (f2.6 x11). Filters: Chroma 5nm Ha filter. Moon: 0% Introduction. It’s now been over a week since the “never ending” clear skies went away. With the full moon approaching I saw an opportunity to maybe get out for a few early morning hours after the moon had set. The skies were clearing when I went to bed and the Devils Orb was already giving the appearance of daylight outside. I had a short restless sleep with the occasional peek to see if the moon was still lighting the edges of my bedroom curtains. Once I was satisfied that it had gone and having taken a few minutes to “motivate myself”, I slipped out from the warm bed and headed downstairs to get dressed. It was pretty windy outside which meant the roll-off shed would not be used tonight so I prepared the Borg107 for a trip outside onto the patio. It took me 20 minutes to get ready before I relayed my kit outside. I quickly performed a 2-star alignment for the Skywatcher AZGTi mount and headed to M45 to test it out… The Pleiades were all bright and sparkly in my fov set against a lovely black background (“looks good” I thought to myself). I had no real plan for the session, so I decided to look at the brightest areas of Orion plus some of the larger Sharpless from my “Best of Sharpless”. I added the Night Vision PVS-14 to the TeleVue 55mm Plossl and added the Chroma 5nm Ha narrowband filter to the front of my 2” diagonal. NGC2244/Rosette. Where else to start but my favourite nebula – The Rosette! It appeared bright and mid-sized (at x11 magnification). Thin bright lanes seemed to trace out the “petals of a flower”. Multi-toned fainter nebula filled in the gaps, then with the dark black central hole and cluster to complete the view. I lingered a while before slewing down and into three spread-out nebula patches (sh2-280, 282 & 284). They are all different which makes them more appealing. The first is a circular patch with two small dark circular shapes inside (sh2-280), then we have an oblong shaped patch (sh2-282), finally on the other side of a bright star we arrive at the circular patch sh2-284. NGC2264/Cone/Fox-Fur nebula. Now for the first “surprise bonus” of the night. I centred on NGC2264 and when I looked in the eyepiece I found the fov filled with faint multi-textured nebula. I located the MINUTE Cone nebula, it was very tiny but a clear black triangle nevertheless! I traced the parent Fox Fur into what looked like a “comma” shape. This comma shape was sitting above a right angled long thick lane. Below this I found a mid-sized curved lane and followed this down and left to arrive back at the Rosette. I decided to make a sketch of the large area just covered as the individual segments were so clear to see (and you do the daftest things when only half awake!) I found the Xmas tree in the tail (of the comma) slightly brighter. I noted a dark lane running through the comma tail section. IC405 Flaming star/IC410/sh2-230 I have had recent success with the sh2-230 undefined area around IC410/405 with the big dob. So it was time to see what the 4” aperture of the Borg could tease out of this region. This is a beautiful detailed large section that really comes out well under low x11 magnification. IC405 and IC410 are immediately obvious. The magnificence (intricate detail) of the upper head section is not so striking at this low magnification but you then notice that the Flame is larger than expected and in fact has an extra patch that seems to extend the tail section further out. IC410 sits by the side and has the appearance of “a mask”, I see two black eyes cutting into the small bright shape. Above IC410 there are two tiny patches (Spider and Fly) then above them I see a large faint circular patch (unknown). To the left of this and above the Flame is a double curved lane which has several brighter sections visible within it (sh2-230) which I have seen before. But my eye is drawn further left and up where there appears to be a huge circular edge (unknown). NGC1499 California. While looking at Sky Safari, I decide to see NGC1499 (another nebula where the big dob has been working hard recently). Wow, this area is great at low magnification. The “traditional” section of the California is the brightest and easily seen in its entirety but it’s the large extension section to the right (that must be at least the same length again!). Then while examining the tail and crown sections at the left end, I begin to notice a huge structure that seems to sit behind the California nebula. I sketch out what I can see. This background section is vertical where the California appears horizontal. It is faint and has curves under the California where it seems to meet a large faint patch (that has 6 bright stars inside), I add these to the sketch… IC2177 Seagull nebula. Looking for big and bright nebula, I choose to see the Seagull next… The traditional “head and shoulders” fills the fov. I slew around and trace out a large additional structure leaving the “top shoulder” and travelling right and then down to finish at an extended “foot” patch just above the Duck nebula. I sketch out the Seagull and then hunt around for any patches (I know there are plenty to small Sharpless around here). I find two small patches at the end of an extended “leg” section (I thought that one of these was Thor’s Helmet but after slewing to that later then I think I am wrong so I need to revisit and sort out what they are?) Sh2-240 Spagetti. I pick a large nebula from the best of Sharpless, sh2-240 next. It appears as a large circular faint shape. There is a central vertical zig-zag section and I see several hortizontal-ish black lanes travelling through the patch (as I get my eye in). There is definitely lots to see here and its deserving of its place in the “best of Sharpless”. M42/M43/NGC1973, Orion and the Running Man. Okay, I’ve waited long enough! I slew to NGC1973. The only thing you see at the eyepiece initially is M42 of course! It’s so bright and wonderfully detailed. At this low magnification it reminds me of a “bird in flight” with bended wings. The “fish head” is the brightest section but I am fond of the blackness that spews from the fish head and seems to spread out and around M43 next door, it is black as black can be. M43 has an intricate shape inside its almost complete circular patch, but I speed by to seek out the Running man. Tonight the bright patch is clear as day and as I look on a black shape within the bright patch comes and goes, it’s not a “pair of legs” but it’s a black patch within nevertheless. Flame/IC434/Horsehead. I slew directly up from M42 and a bright patch comes into view, over to the right a bit and there is IC434 bright and thick. The horsehead is tiny but clearly visible and having a decent shape tonight. However, I am completely drawn to the long nebula bend section to the left which runs down from the Flame too. I do not remember noticing this section before but it’s been a year since Orion was here and I cannot remember everything that I see! I now manually slew up from the Flame to find a thick horizontal nebula lane running across the full fov. I follow it right and then down and back under until I find myself back at the Orion nebula (M42). I guess this is Barnards Loop. I had earlier searched for it to the left of Alnitak (as that’s where it is with the dob but this “star diagonal” used in refractors regularly sends me the wrong way when I try to retrace the big dob steps! Angel Fish – Huge and bright. Way too big to see the fish at x11 magnification. I do my best to tease out some features but it is just too huge! NGC2174/Monkey’s head. Instead, I move onto the Monkeys Head. It appears small and bright but as usual I see “Mickey Mouse” with the refractor and star diagonal turning things around. I slew around and pick out two patches above, one is sh2-247 the other is unknown. I slew below and find the wonderful tiny triple nebula sh2-254,255 & 257 (another Best of Sharpless member). NGC2395 Medusa – A small shimmering crescent moon shape is observed. M1 Crab – A small shimmering patch. With time at the eyepiece I see a bright circle around the outside and the occasional jumping line details within but cannot hold the interior in my view. NGC2359 Thor – A small faintish semi-circle. IC443/IC444, sh2-249 – The triplet of nebulas all fit into the fov and are a lovely sight that takes a good while to look around and take it all in. The Jelly fish (IC443) has lovely “tenticles” section that breaks backwards RHS. There is a small bright patch directly in front of IC443 (IC444) and then behind this the large oblong nebula structure sh2-249. I see the fine black lanes within sh2-249 next to Tejat Posterior (bright star). Sh2-265 – Picking another large Sharpless object, I headed for SAO 112667. I found a small bright patch (sh2-263) then above that a huge bright nebula that after slewing around, reminded me of a “walkie-talkie”. It had a pointed section at the upper LHS. And an interesting double lane at the lower sections. Sh2-260 – Next I picked sh2-260 (which I have only ever seen with the big dob). I slewed to SAO 112142 where I discovered a very large faint nebula shape. It was larger than the fov and seemed to appear as a “thin teardrop” shape. I cannot find any images of this so at the moment it is unknown to me. Epilogue. I noticed the sky brightening from around 0550hrs so I headed for a last look at the Rosette and Flaming Star regions before deciding to pack up at 0600hrs. I am glad that I made the effort to get up as I felt like I got “more than I imagined” from my session (which sent me back to bed happy, if a little cold – at least I had my hot water bottle to bring my feet back to life). I think that I have concluded that I need to get the widefield Borg 107FL out more frequently, when it’s cold then the dob in the shed is a much more appealing thought. - I have added an unexpected 7 entries to the “Ag1-xx” nebula catalog for the unknown/extra patches that I will need to come back and confirm… (up to 97 entries now). I also now have some lingering memories to help me through the barren spell of the full moon (out here in the dark countryside, the full moon is a real killer!). Hope you enjoyed the read and my sketches! Alan
  16. Yep, the Chroma filters are great. I like the way they give higher performance at low gain settings, this really helps to pull out the black features within nebulae (as you lower the gain then you increase signal to noise ratio). This really helps tease out the finer details. It would be nice to test out a 3nm but I can’t imagine that I would get a great jump in extra detail over the 5nm for the cost outlay. I am happy with my current equipment and it will soon be a whole year since I spent any money on Astro kit !!! Alan
  17. Dates: 26th thru 30th Oct 2019. (Over twenty hours of observing time!!!) Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (f2 x38), Panoptic 27mm (f4 x77). Filters: Chroma 5nm Ha filter. It’s a Miracle! I have been out observing on each of the last five nights racking up a combined time outside of over twenty hours – It’s a long time since I have had such a good run. I have written 17 pages of notes during my sessions too… I have observed many objects of different types during this time outside. So, I am going to divide up this report into object type sections so you can scroll to objects of your favorite kind… Planetary Nebula. First up planetary nebula, this is an object type that I rarely write about but having bumped into a few of these while out nebula hunting with my 5nm narrowband Ha filter combined with my PVS-14 night vision, I decided to build a Sky Safari observing list based on “The Brightest Planetary Nebulae Observing Atlas” by Massimo Zecchin and get out and observe them with a plan. The eyepiece attached to the PVS-14 for these observations was a 27mm Panoptic yielding x77 magnification. NGC6826 (Blinking Planetary) – Very bright solid ball with a thin halo of lighter shade. NGC7027 (Magic Carpet) – small bright ball, there is either a fine line running through it or it is two-toned. Has a detached faint circle around it. NGC7048 (Disk Ghost) – small dim circular patch made up of “dancing lines”. Looks alive. NGC7026 (Cheeseburger) – Tiny and bright. Made of two patches with a haze on either side. Reminds me of an “overhead shot of a rowing boat with oars out either side in the water”. NGC7008 (Fetus) – small dim, almost square shaped patch. Black circle at centre then dominated by thick bright outer layer (does not go all around the outside). NGC6905 (Blue Flash) – tiny, dim patch made of moving lines. Looks brighter on one side. NGC6543 (Cat’s Eye) – small bright patch. Tiny dark spot in the centre. Seems to have a thin layer of lighter dancing lines all around the outside. NGC7662 (Blue Snowball) – tiny. Very bright solid ball. There is a faint detached outer circle. NGC40 (Bow Tie) – Excellent. Very bright with two curved sides. The inside is filled with fuzzy stuff that is leaking out from both ends. There is a small circle at the centre. M76 (Little Dumbbell) – Looks like a “box kite”. Brighter patches at either end, connected by fainter central oblong section. NGC1501 (Oyster) – Tiny and bright. Looks alive. Reminds me of a bright “woolen ball”. IC2149 (Red Sword) – very tiny but bright. Has a small circle around it. NGC1514 (Crystal Ball) – star inside a black circle with multi-toned nebula shell encircling that. Nebula is multi-lined and shimmering. Looks alive. NGC7139 – Small mesmerizing ball. Shimmering jumping lines within. Alive. The "alive" planetary nebulae are great to look at, they are literally moving and dancing around in the fov. 😀 Comets. Another object that I has not been on my radar for several months! Well, I managed to find three over the last few nights. C/2017 T2 (PANSTARRS) – With the 55mm Plossl (x38) it was small but easily seen. C/2018 N2 (ASASSN) – With the 27mm Panoptic I found a decent sized fuzzy blob to the side of a star. It was easily seen and the best of the three. 😀 C/114P Wiseman-Skiff – Even with the 27mm Panoptic, this was a tough object to find. I needed to turn the gain up to the max but I found it exactly where Sky Safari said it should be! Galaxies. Now the great square is in the south, there are some of the brightest night sky galaxies available for observing. I have observed the following NGC6946, 6643, 6503, 6140, 6015, Stephans Quintet, 7331, 185, 147, 278, M110, M32/32, M33, NGC404, IC10, NGC669, 684, 672, 972, 925, 949, 1023, 891, 1160, 1161, 7814, M74. It’s a decent list, but the outcome has been disappointment. The only galaxies that I observed the spiral arms were M33, 31, 74, NGC891, 6643, 7331. Here are a few descriptions from my notes: NGC6946 (Fireworks) – With the 55mm Plossl and no filters, I could see the twin fingered arms coming out from the core around the back. I got hints of a third fainter arm coming out underneath. NGC6643 – A small galaxy. You can easily see the core and surrounding halo. There were some faint anti-clockwise arms beyond the halo but they were tough to see in direct vision. NGC6503 – small and bright. Slightly edge-on. Tiny bright core with large halo surrounding. Hints of black lanes within the outer halo. Stephans Quintet – All 5 galaxies easily seen with the 55mm Plossl (x38). There was even a sixth galaxy in the fov (NGC7320C)! NGC7331 – bright core, slightly dimmer halo surrounding. Swirly fainter disc beyond that. Hints of a lane top-side and a black patch (usually signifies that arms are there) behind core on outer edge. I could see the four “flea” galaxies that sit to the LHS. NGC891 – Wonderful. Large edge-on galaxy with swollen core section and thick black lane running its full length in direct vision. NGC751 – A strange one, with the appearance of a double-core. Sky Safari says its two galaxies NGC750 & 751). M74 – At first I see a mid-sized fuzzy patch but I keep looking. I see a circle around the core appear first, then an arm seems to leave at 3o’clock and curve up and left. Then I see another arm at 9o’clock going out and down anti-clockwise. I note a four star rectangle and add it to my reference sketch. I can see images that confirm the arms on the internet. IC10 - I had already observed this underwhelming galaxy earlier in the session when I happened upon it again by chance (whilst I had the 5nm Ha filter fitted and was just sky scanning) and found it as a pleasing patch, it was only when checking Sky Safari that I found out it was the IC10 galaxy that I was looking at. It appeared so much clearer with the Ha filter that I wondered what the bigger galaxies on offer would look like in Ha? Lets try Andromeda & Triangulum in H-alpha. I have written about my experiences with M31 and M33 many times before, so I won’t be repeating myself today. Instead, I want to talk about an H-alpha experiment that I carried out over a couple of hours with M31 & M33 as my targets. I loaded my Chroma 5nm Ha filter into the Paracorr2, then added the 55mm Plossl for maximum image brightness and pointed at M33. To my surprise there was a very large galaxy sitting in the fov with many fuzzy shapes abounding. It took a few minutes to take it all in and start to recognize NGC604 and work back from there… With no Ha filter then the big reverse S of the main arms is clear in direct vision, now the arms are not clear but if I look carefully then I can trace tiny Ha patches that are marking out the arms in the fov. I decided to start sketching these patches and add the occasional curve where I was seeing “implied” arm structure. It was quite a surprise just how far out from the core some of these Ha patches are located, signifying that actual physical size of M33 is larger that we may think when visually observing our neighbour. Here is my sketch: Onto M31, where the results were less impressive but I was able to see the galaxy and some Ha components within so it was not a waste of time at all. I noted three Ha patches in the upper sections of M31 but it was the lower sections that were a bit of a revelation. Regular observers of M31 will know that it’s a dead loss below the core to see very much at all! Well, in Ha the lower section can match the upper section and in fact I saw a greater number of Ha patches in the lower section including a couple of really big ones. Here are my sketches of the two halves of M31: Nebulae. I spent many hours looking at the many large and small nebulae in the Milky Way from Cygnus to Orion. I have written about them many times before and will not do so today. I was also able to spend some time scanning the “empty spaces” in Sky Safari looking for objects that I could find with the night vision and marking them for the "AG1-" night vision object catalog that I am continuing to work on... I am now up to 82 objects having added a further 38 objects during October. I have also managed to revisit 52 of the objects to confirm their existence and descriptions. Time to catch up on my sleep. The weather forecast seems to say wet weather until full moon, so it looks like I will be stuck inside for the next couple of weeks, guess there is no pleasure without pain! Clear Skies, Alan
  18. Time does not stand still... It has been 17 months since I wrote the original version of the above named article and there have been a few changes in the intervening time period… 1. I now have 17 months more a-focal experience of using a telescope with a night vision device attached directly to the eyepiece. 2. A new forum has been created for the discussion of such “Electronic Assisted” observing equipment on this website. So I decided to revise my article and post it in this new “most applicable” forum. Let us start with the basics… What is a-focal observing? “a-focal observing” simply means that the night vision device is attached directly to an eyepiece (after the focal point of the telescope). You are placing the night vision device’s objective at the exit pupil point in the light path. The easiest way to achieve this is the use the “TNV-14 Eyepiece Adapter” (available from Tele Vue). This adapter has threads on either side to connect (1) any Dioptrx accepting Tele Vue eyepiece to (2) a PVS-14 Night Vision device. http://www.televue.com/engine/TV3b_page.asp?id=36 Here is a picture of a Tele Vue 55mm Plossl connected to a PVS-14 using the TNV-14 adapter. To perform “a-focal” observing we need to simply insert this “stack” into any telescope focuser. If the attached eyepiece can achieve focus then there will be a focused image available to view in the PVS-14. Here we see the stack attached to my 20” dobsonian and my 107mm Borg refractor… What are the advantages of a-focal? The biggest advantage is that you WILL be able to reach focus in any scope. Unlike other options you are simply placing the night vision at the point of the exit pupil. For Newtonians, this is a big point. Fundamentals of a-focal observing. Now we are past the basics, we have some slight more complicated “fundamentals” to get our heads around… 1. The PVS-14 night vision device is designed to work at a focal ratio of f1.2 (which is very fast). To get the most from the device then we need to aim to send light from the eyepiece as fast as possible to take maximum advantage of the night vision device. A faster focal ratio results in a brighter image, a slower focal ratio results in a dimmer image. - Here we have been given a “lucky break”. Because the PVS-14 has an effective focal length of around 26mm, if we use any eyepiece with a focal length greater than 26mm then the “effective” focal ratio of our system gets “magically” increased. [I will show how we calculate this effective focal ratio shortly but think of this on a par with adding a focal reducer into the light train]. Unfortunately, any eyepiece with a focal length less than 26mm will decrease this “effective” focal ratio of our system. 2. The PVS-14 has a fixed forty (40) degree field of view. It does not matter how wide field our eyepiece is, the night vision device will only ever show the centre forty degrees. This means that you don’t need 100 degree Ethos or 82 degree Nagler eyepieces, narrower field of view Plossl, Panoptics & DeLite’s will be fine. - Again, don’t panic! There will be so much to see in the forty degrees that it will feel like 100 degrees. I have come from 100 degree eyepieces and I have never once wondered where my huge FOV went 3. Eyepiece eye relief is important. You need eyepieces with enough eye relief to match the distance from the top lens surface of the eyepiece to the position of the night vision objective lens. Too much or too little eye relief will result in loss or distortion to the outer edges. What is the minimum set of eyepieces that I need? I use a total of four (4) Tele Vue eyepieces with my Night Vision device: 1. Tele Vue 55mm Plossl. This is my main work horse eyepiece. I use this eyepiece for >90% of my observing time. The reason it is my most used eyepiece is that it gives my telescopes the fastest possible “effective focal ratio” (which results in the brightest possible image at the eyepiece). In simple terms think of this eyepiece as being able to double the speed of your telescope (like a 0.5x reducer). I use this eyepiece for nebulae, galaxies & open clusters. 2. Tele Vue 35mm Panoptic. I use this eyepiece occasionally when I want more magnification but still want a bright accelerated image (it acts like a 0.7x reducer for the effective focal ratio). An alternative to this eyepiece would be the Panoptic 41mm - I use the 35mm because it’s half the weight of the 41mm! I use this eyepiece for nebulas, galaxies, comets, large open clusters. 3. Tele Vue Panoptic 27mm. I use this eyepiece again for greater magnification, usually for supernovae, globulars, comets & open clusters. I do not use this for nebulas and galaxies as the effective focal ratio is now too low and details are becoming lost at the eyepiece. 4. Tele Vue DeLite 18.2mm. This is my least used eyepiece (as its focal length is smaller than the 26mm of the night vision device). In use, it has the effect of slowing my effective focal ratio and producing a dimmer image. It does however produce about the maximum useable magnification with my night vision a-focal setup and I have been successful using it for faint tiny supernovae and bright globular clusters. What about the huge exit pupils? [Exit pupil is the width of the light beam being emitted from the top of the eyepiece and traditionally astronomers baulk at anything wider that the width of the astronomers own eye pupil as it is not possible for our eye to consume the whole of the light beam] [Exit pupil is calculated as the eyepiece focal length divided by the telescope focal ratio so a 55mm Plossl in an f4 scope will produce a light beam 13.75mm wide] As the night vision objective lens is 20mm wide then it can take all that light in and process it with room to spare! Whilst your eye pupil would be flooded and loads of light wasted, no light is wasted in this case. But as the eyepiece focal lengths get shorter (and the exit pupils get smaller too), the night vision device soon starts to become starved of light. How do I calculate this “eyepiece focal ratio” exactly? Now seems the right time to show the maths to calculate the “effective” focal ratio of your telescope/night vision setup: Effective focal ratio = NVD / (EPFL / TFR) where NVD = night vision device focal length = 26mm EPFL = eyepiece focal length TFR = telescope focal ratio As an example, if we have a telescope with a focal ratio of f4, the 55mm Plossl will produce an “effective” focal ratio of f1.9. [Effective focal ratio = 26/ (55/4) =1.9] Does the focal ratio of my scope actually change? The answer is NO. These changes in “effective” focal ratio that I mention only happen inside the night vision device. If your scope is f4 then it will remain f4. Is a-focal observing, low magnification observing? Simple answer = Yes it is. You need to get as much light as possible into the night vision device as fast as you can get it to go. All of the photons that you can get into the device will be amplified by the night vision device enabling you to see views containing previously unseen detail. In some cases, the amount of new detail on offer will be overwhelming! At first, you will want to change eyepieces to achieve greater magnification but you soon discover that you actually see less detail (due to loss of effective focal ratio and exit pupil) so you soon return to the longer focal length eyepieces. How do I calculate the magnification that each eyepiece will give me? There is no change here. Take your telescope focal length and divide by eyepiece focal length. If your scope has a focal length of 1800mm then you would get the following magnifications from my eyepiece set: - 55mm Plossl (1800/55 = x33) - 35mm Panoptic (1800/35 = x52) - 27mm Panoptic (1800/27 = x67) - 18.2mm DeLite (1800/18.2 = x99) How do I calculate the TFOV? I used Sky Safari for this. I setup my eyepieces in the “equipment” section using a setting of 40 degrees for the fov and it did the rest… Can I use a coma corrector with night vision? If your telescope has a fast focal ratio and you find that you need a coma corrector now then you will still need it for use with night vision. I used a Tele Vue Paracorr2 with my 20” dobsonian before I had night vision and I am still using it with Night Vision. In a big reflector, the best place for filters in the light path remains on the bottom of the Paracorr. What about filters? This brings us nicely onto every astronomers “favourite” topic – filters! When combined with filters, night vision devices can allow us to not only see what was not visible before but also to steal back some darkness by blocking out our old enemy, the moon! In the Cumbrian countryside, the night sky has an SQL of around 21.6, class 4 Bortle. Please take this into account when reading my experiences as your SQM may not be the same as mine. 1. General observing – For general observing, I do not use any filters as the best results are achieved by letting all the light into the night vision device. The PVS-14 has manual GAIN which means there is a knob that can be turned to decrease the gain and darken the image at the eyepiece – this is the only filter that I use in general observing. Moon – If the moon is up then I add a Baader 610nm Red filter into the light path. This is a good filter for reducing the effects of the moon on the sky background. It can also be effective if viewing low to the horizon where light pollution can be an issue. 2. Filters for observing Nebulae For nebulae viewing, a narrowband Ha filter in mandatory. I have tried 12nm, 6nm and 5nm and my preferred choice of bandwidth is the 5nm. As this filter is the “key” to seeing nebula then please do not scrimp of a “cheapie”. If you want to get the maximum from your expensive night vision device then only consider top brands such as Chroma, Astrodon, Astronomik or Baader. I am currently using a Chroma 5nm Ha narrowband filter. Your choice of Ha narrowband filter will directly affect whether you see some of the fainter nebulae objects or you do not see them! 3. Filters for observing Galaxies For galaxy viewing, there is no filter that can improve the unfiltered view. However, if the moon is up then I use either the Baader 610nm red filter or an Astronomik UHC Visual filter. If you are viewing tiny smudges then either are okay, if you are viewing larger galaxies with spiral arms, then I find that the Astronomik UHC Visual filter gives slightly more spiral arms than the 610nm red. Both beat unfiltered viewing if the moon is up. @GavStar is using a “Baader IR pass” (685nm) filter from his city location for all non-Nebula targets to cut out the light pollution. Which night vision units can I connect to my telescope for “a-focal” observing? As a UK based astronomer there are very few options for us to purchase a Night Vision Device with the latest military specifications. The Tele Vue adapter works with the PVS-14 night vision device so this led me in that direction. I purchased my PVS-14 from www.actinblack.com based in Luxembourg. Please do read my article on “Understanding Night Vision Tube Specs a little better” and do be prepared to wait a month or two for actinblack to get a new batch of tubes into stock (from which you can then pick the best one for astronomy use). I had to wait two months for a new batch of Photonis tubes to come into stock before I was sent three tube specification sheets to choose from via email. Having selected my tube then it was delivered to me in under a week from placing the order. Which telescope do I need for Night Vision? This is a good question and one that will be debated long into the future. My opinion is that the best telescopes for a-focal night vision use are telescopes with fast focal ratio. I am using an f3.6 dobsonian and an f5.6 refractor. Our goal is to achieve the brightest possible image at the eyepiece and focal ratio is the key to achieve that. As we can see from above, there is a rather restricted set of eyepieces needed for night vision astronomy but if we pair these eyepieces with telescopes of varying focal lengths then we can get a wide range of actual field of views and magnifications. This drove my minimal set to two telescopes, one long focal length dobsonian with good aperture and largest possible magnifications (with long focal length eyepieces) and one short focal length refractor for wide field with decent apperture (> 4") and light enough for travel. What can I see using Night Vision a-focally? At this point, I want to point you to some of the many posts from @GavStar available on this website. His images do reflect what I can see visually with my two setups. Let me go on to summarize what I have been seeing in the last 17 months since the initial article. Nebulae I have now almost completed the full Sharpless catalog (303 of 313 objects). The only ones that I have not seen are the ones that are too low to my horizon! Galaxies I am working through the 200 brightest galaxies available in the skies above us. This project is more than half way complete and so far I have observed the spiral arms of 68 galaxies with direct vision. Supernovae Last year I viewed 17 supernovae, down to a magnitude of 16.8 Globular Clusters I have so far failed to give sufficient time to Globulars, but their brightness means that I have been able to see some of the smallest and faintest on offer above us. I will get to these once my Galaxy project is completed. Comets Night Vision works well on comets, in a side-by-side test with traditional eyepieces, I saw better results with the night vision device. Open Clusters Night Vision gives great results with open clusters. The smallest ones just jump out at the eyepiece as you nudge around. Planets Failure – night vision is no good for planets. They are too bright. Moon Failure – night vision is no good for the moon. It is too bright. Here are a few links to some of my reports (there are many more if you use the search facility)... Do you still use eyepieces for observing? My eyepiece case has been mostly sold off now. I have a set of short focal length DeLite eyepieces for planetary and I have some eyepiece pairs for solar observing with my Lunt LS60. I use eyepieces to complete the 2-star alignments of my telescopes then it’s become automatic to just switch straight to the Tele Vue Plossl and my night vision to get into my nights observing. With the GAIN turned down it really is no different to using an eyepiece and you just see so much more… Hope this helps somebody, Alan
  19. Date: Monday 7th October 2019. 2340-0350hrs. Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS. Eyepieces: Plossl 55mm (f2 x38). Filters: Chroma 5nm Ha filter, Astronomik UHC, Baader 610nm Red. Moon: 70% (until 0100am) Introduction With the full moon quickly approaching, the chances of getting outside under a dark sky are diminishing rapidly (for the next two weeks anyway). Last night was forecast clear and by 10pm it was 80% clear with a big old moon shining brightly in the south at about 40 degrees above the horizon. I checked the clearoutside website and saw the moon setting time was 1am so decided to wait a while before going outside… By 2320, I checked again and could see the Moon was behind some clouds so decided to head outside. After spending the last few months in the rear corner of the shed, I had yesterday re-located the big dob more centrally so I could access Cassiopeia (overhead) unimpeded by the shed roof apex. It took me 10 minutes to get the big dob setup & connected to Sky Safari 5 (via my AstroDevices Nexus) ready for the 2-star alignment. I pushed back the shed roof and looked for alignment stars, I noticed that the Great Square was now high and Southern and the thought of M33 popped into my head. Perhaps I would chance a visit to the big galaxies (even though the moon was up). Part 1 - Galaxy Appetiser. Once 2-star alignment was completed, I fitted the PVS-14 Night Vision device to a TeleVue 55mm Plossl and put it into the focuser. I nudged over to M33 using Sky Safari as my guide and centred it up. M33 (unfiltered) – At first I could see what appeared as a large dust cloud, I looked for NGC604 out on the tip of the spiral arm but it was not easily spotted… As I continued to look, I noticed a long curved spiral arm headed south from the central core and it dawned on me that I had forgotten just how large this galaxy is at the eyepiece (even at x38 with the 55mm Plossl), as I traced the arm then I found NGC604 which was small and bright sitting next to a star! The next thing I noticed was a tiny NGC/IC patch sitting at 9’o clock from the core. I looked hard for the upper arm but there was not much showing on the upper side of the central core patch. M33 (Baader 610nm Red) – I decided to try to filter the moonlight out of the view and added the Baader Red filter to the front of my Paracorr2. Once I had refocused, I immediately noticed an improvement in the upper arm view but the lower arm seemed to be less visible than before. I could however see two clear NGC small patches in the path of the lower arm. M33 (Astronomik UHC) – I swapped filters for the Astronomik UHC visual filter which has a slightly wider bandpass than the Baader red and was rewarded with my best view. The upper arm improved once again and I could now see a faint (& large) backwards “S” curve in direct vision. M110 (Astronomik UHC) – I decided to checkout Andromeda and pushed the scope to its location. When I looked in the eyepiece, I saw a mid-size oval patch (it had to be M110). Unusually (at least as I remember it) M110 had a two-tone core, there was a bright small central piece which was surrounded by a mid-brightness halo and finally the fainter oval of the outer galaxy. This may have been my best view of M110! [It is worth noting that I changed my secondary mirror in July from 104mm to 120mm and I am seeing many objects better than I remember seeing them before so I am putting the improved M110 down to the increased secondary mirror size – the 55mm Plossl requires loads of out-focus so I decided to send a wider light cone down the focuser] M31 (Astronomik UHC) – I nudged right to M31 and found a super large central core with 2 vertical black dust lanes sitting on the LHS. I traced the dust lanes up, the first cuts across through the galaxy just after M32 whilst the second continues up to a sharper point further up. The curve of the dark lane at the upper tip seemed to curve back down out beyond M32 (as if M32 sits within the M31 disk), this dark lane quickly disappears so I could not trace it down as far as M32. Below the core, it was much harder to trace the dark lanes but I could trace the edges of the galaxy disk which were faint but noticeable. Part 2 – Search for visible nebula (not in the Sharpless catalog). My latest project is the creation of a new catalog of nebula objects that are visible with Night Vision plus Ha narrowband filter and not present in the 313 Sharpless catalog. The AG1-x catalog has 56 objects so far... With the Dob in its new central location, it was time to resume my push-pull systematic scanning of the Milky Way above me. I added the Chroma 5nm Ha narrowband filter to the Paracorr2. Unfortunately, I could not easily access my planned starting point as Cygnus was now quite westerly and the shed wall was blocking plenty of the primary mirror in that direction. I reset my starting point higher towards the zenith but still westerly and started to scan backwards…up then forwards… up NGC 7008 – I found a tiny bright “flying saucer” which I identified as NGC7008 by glancing at Sky Safari. GSC 4258-1810 – At this location there is a small patch which Sky Safari seemed to indicate might be galaxy NGC6952. But as I looked around the fov, I found that I could see a second patch (the galaxy). Checking the internet, I see that NGC6952 is also classified as NGC6951, I can see an image of NGC6951 where there is nebula visible to the side. TYC 3194-1302-1 – At this star location, I found two bright “angel wings”. They were mid-size in the fov and were bright. Nudging around, I could see that they were part of a much larger structure (which turned out to be sh2-119). NGC 7048 – I found a small bright circle at this location. A planetary nebula. It was very interesting many shimmering lines and variations seen within the small visible circle. Sh2-129 – Next I bumped into a beautiful thick curved section with nice detailing on the edges of the large nebula. Checking Sky Safari, I found it to be sh2-129. It’s a lovely object (one half is similar to the Witch’s Broom in the Veil) while the second curve is much less defined but wide and easily seen/traced. IC1396 – Next, I bumped into an old favourite, the Elephant Trunk. I was expecting a good view with the dob relocated but what I got was a WONDERFUL view. I spent many minutes slowly combing this large object and noting the many black hydrogen holes and lanes visible seemingly all over this large bright patch. I also noted several bright highlights that stood out as brighter than the general bright background. I opened up an image of IC1396 from Sky Safari and made a second sweep across the object to check out each and every one of the black patches seen on the image. The two sections of the elephant truck were very clear and there was a third dark lane sitting alongside them that kept taking my eye too. [Time now 0140hrs – Moon has gone] TYC 3968-1328-1 – At this location, I found a faint vertical lane of nebula. It led into a curved horizontal piece higher up. Sh2-132 – Next, I bumped into a very bright and interesting nebula (Sky Safari shown sh2-132) which turned out to be the “Lion”. The bright mane section really seemed to fill the fov with some lovely black detailing and the occasional brighter line. I traced the back and then the tail, down past the hind quarters and left through the faint legs area to just about see the faint head/snout section. Nice. Sh2-135 – Bright set of “angel wings”. Sh2-134 – Covers a huge area. Not a complete structure, you just keep bumping into small sections here and there. Sh2-138 (GSC 3995-1279) – tiny patch next to a star. Sh2-139 (GSCII N0123010-13835) – small faint patch near a star. GSC3997-0919 – I found a large faint patch at this location. Sh2-152 & sh2-153 – Next, I came upon a nice nebula combo (“Whale & baby” as I call them). Sh2-154 – I thought I had found a bright new piece of nebula when I happened upon a bright star cluster with a long leading edge running behind (LHS). It was wide and very bright but Sky Safari was happy to inform me that it was sh2-154! Cave – I saw the Cave nearby on the IPad and nudged over. Wow, maybe my best view. Not because the Cave was good. The Cave was the Cave but because of all the extra nebula that was visible out to both sides over large distances. There were some nice black cut-outs within this expanded large area. [Time now 0217hrs] NGC7380 Wizard – The Wizard is my next unplanned target. Instantly recognizable. Bright and beautiful with so many intricate details to examine, it really takes a few minutes to do it justice. As I drink up its finery, I am drawn to a large black “t-shirt” section that is standing out just to the LHS of the Wizard, so black, its keeps drawing my eye… Bubble – Wowsers, I had a great view (my best ever) of the Bubble last new moon, it was memorable not for the bubble itself but just for the huge “head” and “torso” of the “Gladiator” that filled the FOV. My luck was in, the full Gladiator was back and I spent a few minutes taking it all in. Its strange that 12 months ago, the joy was seeing the “bubble” but now the bubble is just seen as part of this larger Gladiator and does not really stand out from the remainder of this large beautiful area! Sh2-158, sh2-159, sh2-157, sh2-161 & sh2-163 – I move around this rich area of nebulosity. Sh2-157 (the pincers) is always worth a lingering visit, there is some exquisite detail in the wide head section and it’s always nice to bump into the tiny star clusters out at the “sharp” end. Sh2-161 is the Sharpless designation for this whole area encompassing all these smaller brighter objects, as you nudge around then you can still find smaller separate unclassified nebula sections that belong to sh2-161. ARO115 – I scan around and bump into a tiny faint patch, Sky Safari says “ARO 115”. Sh2-165, sh2-170 – After passing by sh2-165, I find sh2-170 which is in my “best of Sharpless” list. It’s a beautiful mid-size patch with a central black patch with two “eye like” stars within. The black patch is surrounded by a wide nebula halo. Nice. Part 3 – It’s late, time for some “bright” eye candy… Pacman – Another recent Wowser from new moon revisited. I am not disappointed! The black lane looks like an upside down “sleek black cat” with 2 pointy ears. The nebula to the LHS is huge and almost white with brightness whereas there is “not a lot” to the RHS of the black cat. The outer edges are a fainter shade and extend way out to the LHS. The lower edge is a lovely multi-shaded section that really attracts my eye. Heart – With the dob relocated, I can now reach the Heart & Soul. And I am not disappointed except for the fact that it’s just so big, it really is a nudge-nudge challenge to get around the whole object and not miss anything! The “mole head” is upside down but I see a small patch just to the side and a black hole section. It looks like “the mole is trying to post a small patch into a round bucket”. Over in the central “bright city” section, I see many shimmering small curvy lanes, it’s hard to count them as they overlap and shimmer over each other. I notice many small Sharpless objects dotted around the outer edges “like little boats anchored just off the beach” but I am too short of energy to note and name them individually. Soul – I centre the head and instantly notice that it has a black eye section and a jagged mouth section cutting back into the head. (I can’t remember these but it’s been a year!). I notice a small black hole within the arm/elbow section too. Monkeys Head – Bright and picturesque. I scan around but don’t notice anything that I have not seen before. M1 Crab – The crab is a strange object and improves the longer you look at it. It starts out as a patch with shimmering lanes inside. But if you stop and look the lanes turn into five bubbles that shimmer and jump around as you look at them. This object seems to be “alive”. IC410 – Wowsers. It’s the “Stay Puft Marshmallow Man” from Ghostbusters . A large “Mr. Fluffy” face fills the FOV. It’s so white and it has two black eyes and a black nose hole. Two small bright curvy “tadpoles” sit nearby. California – After visiting the Spider and the Fly, I head over to the California nebula. I am rewarded with a final “best ever” viewing for the night. Wow, I have never seen IC1499 like this! The nebula is literally 3D at the eyepiece. I have to step back and process what I am seeing before heading back to my periscope to spend some time enjoying the view. The sides are seen as white hot almost horizontal lanes then the inner section just seems to fall into the eyepiece which my brain perceives it as steep curving section in then back out at the other side. The small black eye just stands out centrally. I head out to the LHS where the California has a bright “crown” section and look up for the “flap” which is bright and clear. I trace out into deep space of both ends as the nebula seems to never end but just fade away fainter and fainter until it’s gone from view. Epilogue. By now, clouds are coming and going as is the view from the eyepiece. I check the time -0345- and decide that I have had a great night and I will get the roof closed just in case there is a “shower”. I am not too cold, which makes a nice change from last new moon when I felt frozen at the end of my last marathon session. This had prompted me to get out my full winter wardrobe of thick observing clothes and I was happy that I made the right choice. There was a bit of dew when I turned the light on and I had to towel the UTA dry before I packed up and turned on the de-humidifier. Thoughts of the observer. I had not planned on any galaxy viewing so it was nice to get back into them after what seems like 6 months of nebulas. I was pleased with what I saw given that there was plenty of moon about. Do try out your old “Astronomik UHC” as a moon blocker if you have one! I found 6 non-Sharpless nebula and added them into the fledgling “AG1-x” catalog ready for confirmation revisits (I now have a tentative 63 entries). It’s clear from last night sweeping of Cassiopeia, there is nowhere near as much of the Milky Way visible in this area when compared to Cygnus so I will need to work harder and longer to find new (to me) stuff to observe. I can see Orion moving South and now have a burning desire to test out the bigger secondary on the many bright nebula waiting for me in that area of the sky… Hope you had a clear night too. Alan.
  20. Peter, Thanks for all your help in getting me started into the world of Ha observing ! All those observed in the 4" Borg (marked "B") should be doable. Those seen only in the 20" (marked "D" and no "B"), you may need to borrow Gavin's 16" ... Alan
  21. Introduction Having just published my "Best of Sharpless" object list... Here is a full list of the 313 Sharpless objects together with their location information (based on nearest star from Sky Safari) and with a GOTO reference for your mounts (I was using a SynScan handset). For those astronomers out there with a Ha narrowband filter and an urge to get images of "something new" or "something different" then here is something to get your teeth into! I have just spent the last 16 months exploring 303 of 313 Sharpless objects and I had a great time, there are some very rarely observed objects in this list What follows is a data table of all 313 Sharpless objects. For each object the table shows: Sharpless Reference, Observed? (1=YES), Best Of? (1=YES), Physical Size, Scope Used (B=Borg107FL, D=20” Dob), SS Star Ref (An object that I located manually at this star position), Goto ref (Closest SAO, NGC, M object for Goto mounts), Catalog Name (The more famous objects already have a name) In SS? (1= object in Sky Safari, 0=No) Note (details Sky Safari/Bracken errors) Here is the raw excel file: sharpless targets v8.xlsx Hope this helps you find and observe one or more of these wonderful nebula Clear Skies, Alan
  22. Introduction I purchased a Night Vision Monocular in April 2018 to attach to my TeleVue eyepieces and use for astronomy purposes. Initially I purchased an Astronomik 6nm Ha filter (I later switched to a Chroma 5nm Ha filter) to allow me improved views of many visible nebula but I discovered that I now had access to a whole new world of previously invisible (to me) nebula. I discovered that many of these were in the “Sharpless” catalog and began a journey to see how many of the 313 catalog objects that I could find/observe. I wrote an article in the Webb “Deep Sky Observer” (Issue 181) detailing my joy and initial efforts to observe the Sharpless objects using my Night Vision Monocular. Last week, I observed my 303rd Sharpless object. Of the ten outstanding, one does not exist (sh2-214) and nine and very low on my Southern summer horizon (and will be left for a Greek holiday sometime in the future!) so I am ready to publish my findings in the hope that they may assist others who take the same route in the future. Finding the Sharpless Objects Before you can observe an object, you need to find it and get it into the eyepiece (obvious)… My main scope is a 20” push-to Dobsonian which I attach to Sky Safari 5 Pro and push to my chosen targets. I soon discovered that the Sky Safari database only contains 249 entries and a small number of these are in fact erroneous or duplicates. In all, I have had to locate 75 Sharpless objects manually… I would like to call out the book “The Astrophotography Sky Atlas” by Charles Bracken at this point, as my search would have soon been abandoned if it had not been for this book and its great tables of Sharpless object data (at the back). With this data and the galaxymap online explorer, I was able to use sky co-ordinates to find nearby stars (in Sky Safari) and then hunt around that area to finally find and record an accurate positional star. Many Sharpless objects are huge and so I also employed a second widefield scope, a Borg 107FL, which I paired with a Skywatcher AZGTi GOTO mount with SynScan handset. As I found the Sharpless objects, I recorded the nearest SAO catalog star and then used this for the GOTO mount to get the Borg107FL on target. Unfortunately, I discovered that the SynScan handset does not hold the full SAO catalog, so once again there was some “on the fly” rework needed to get the nearest SAO that was in the handset identified and recorded! The Best of the Sharpless catalog Many of the Sharpless objects were underwhelming at the eyepiece (when compared to objects like the Rosette, Gamma Cygni or the Orion nebula) but when you consider how faint and small some of these objects are then there is more to this than just the “visual beauty” perceived at the eyepiece. However, there is no denying that many Sharpless objects are very beautiful at the eyepiece and in many cases are equal or even better that the better known and more photographed Messier nebula objects. I am therefore publishing my “Best Of Sharpless” list, it is entirely based on my own perceptions so feel free to disagree with the objects that I have selected, I will not be offended. My goal is to inspire just one person (who has an Ha filter) to turn their scope to one or more of these objects and for them to observe an object that they have never seen before! What follows is a data table of 115 Sharpless objects (the best of according to me). For each object the table shows: Sharpless Reference, Physical Size, Scope Used (B=Borg 107FL, D=20” Dob), SS Star Ref (An object that I located manually at this star position), Goto ref (Closest SAO, NGC, M object for Goto mounts), Catalog Name (The more famous objects already have a name) Here is the raw excel file, Best Of Sharpless v1.xlsx If you have an Ha filter then I encourage you to give them a try! Alan
  23. Good luck, you won’t find any as I won’t be posting in this section. Sad but true. Alan
  24. I am afraid that this was covered two weeks back when it all got a bit ugly in a “please make them go away” posting by a seasoned observer which resulted in NV users being banned from posting in the general observing forums. The last thing I want is an NV only forum, with 4 NV users in the UK we may as well just arrange to meet directly down the pub! HTH your understanding. Alan
  25. It appears that we NV users are supposed to join in discussions on "live stacking" and other things that are of no interest to us whatsoever! I wont be bothering.
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