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Sharing with you my latest image, The Helix Nebula (NGC7293), AKA "The Eye of god" in narrowband bi-color.
Exposed for multiple nights during October and November 2019 through HII, OIII narrowband filters using my full spectrum modded and cooled Canon 40D DSLR through my 8" Celestron SCT at 2032mm focal length, tracked with a CGEM mount.
Because a OSC sensor was used to expose this image, I was able to extract Hbeta from the HAlpha and OIII subs (in their corresponding blue channel) and stack them to be used as a real Blue channel in the final image. The green component from OIII is the green channel and red component in HAlpha is the red in RGB color mapping. Because of the use of a OSC camera, I did not have to generate a synthetic channel as is usually done with bi-color narrowband images.
Observation 25-26 July 2017
Date: 25-26th July 2017 @ 19:50 – 2:30AEST
Equipment: 14” Skywatcher GOTO Dobsonian, Televue 31mm Nagler T5 , Televue 17mm Ethos, Televue 11mm Nagler T6, Televue 2X Powermate, Baader Neodymium, Baader Contrast Booster, Astronomik UHC filter.
The first thing I noticed from the beginning is that there was more sky glow than I would like, it was quite obvious that the seeing won't be perfect.
I keep hunting for maximum magnification and detail on planets so before observation I re-collimated the Dobsonian from scratch.
This time I put a white piece of paper behind the secondary so it was easier to see if the secondary mirror is circular and centered.
Second step was to use the laser to collimate but noticed that when I touched or span the laser, its reflection changed, so using it is pointless without first collimating the collimator (what da?) and proceeded to use the Cheshire.
As a final step I tweaked the collimation on Saturn and a nearby star.
Saturn: Saturn looked soft and fuzzy. The Cassini division was barely hinting itself in and out of a shade like apparition on the outer edges of the rings.
There were 5 soft moons around it, but I knew that the seeing was too poor to properly test the collimation tonight.
After a disappointing start tonight when comparing to my hope and expectation, while observing Saturn at 150X, at 20:40 (iPhone time, 20:38 "Star Walk" time) a bright satellite flew past and through Saturn. The flyby was not slow but wasn't as fast as a shooting star either. When checking for satellites on the "Star Walk" app, it turned out to be "Envisat".
It is rare views like this that make a view memorable and special, by adding a bit of action to the scene.
After seeing that Saturn looked quite soft and with the considerable amount of sky glow, I wasn't expecting to get the best views so I took the lazy approach to observing tonight and, after accurately star aligning the scope, selected the objects above 40 degrees in order from the "Deep-Sky Tour" option on the SW14 hand controller.
Lagoon Nebula (M8): M8 was visible the same as I saw it last time I was observing and as before the sky glow killed all of the fine detail that I saw back in May. Again the main part of the nebula was visible, the dark lane was there, with a hint of structure with in it, as well as the faint nebulosity around the main “Lagoon” coming into view at 50X and 100X power. During dark nights, there is a lot more visible, especially detail wise within and around the nebula, but unfortunately tonight, that was washed away. As with most nebulae, the best way to view this nebula is by using the UHC filter.
Omega Nebula (M17): At 50X and 100X the “Swan” is easily visible, along with some of the outer nebulae coming into view faintly around the “Swan”, particularly behind it. Higher magnification, 200X, the structure and shading was once again very easily visible within the Swan head and body. The use of the UHC filter is a must on this nebula to see all of the details. Still a lot of detail is visible for such a bright sky glow seeing condition.
Eagle Nebula (M16): The "E" shape was quite easily visible, not as obvious as during a darker night but still visible among the stars in and around the nebula. I’m very sure that at 200X magnification and using the UHC filter, I saw the “dark pillar”, the middle one out of the “Pillars of creation”, the one with “squiggle” at the bottom of it in the photographs. At 100X there was a quite obvious dark shading where the dark pillar is situated.
At first I thought it might be wishful thinking and talking myself into believing that I’m seeing hints of one of the pillars, as the seeing and transparency conditions are not the best, but the more I looked in the area, the more I was seeing a distinct elongated darkening at the correct spot, just under the two brighter stars within the nebula.
Pavo Globular Cluster: The Pavo Globular is a very nice looking Globular cluster. At 200X it looked like a typical globular except that it has, what looks like, more brighter individual stars sprinkled at the foreground with the Globular shimmering behind it, a few scattered stars at the edges and one particularly bright star toward edge at the top left.
This Globular is not as big as 47Tuc or the Omega Cluster but at higher power, it looks just as nice and interesting. This Globular is definitely in my top 3 Globular Clusters to view to date and I will make the effort to image it hopefully in the not too distant future.
Butterfly Cluster: An open star cluster with a bright orange star within that drew attention to itself. At 50-100X magnification it sits nicely within the FOV of both the 31mm Nagler and 17mm Ethos. The Butterfly Cluster is a medium sized open star cluster and with the orange star glowing within it reminds me of two other objects, it sort of resembles the cluster within the center of the Rosette nebula with a touch of the orange jewel from the Jewel Box cluster in Crux.
Trifid Nebula (M20): The nebula was surprisingly easy to see tonight considering the glow, but the dark lanes are easily visible, within the easy to see with direct vision, “Trifid”, the double star in the center is easily split and the blue nebula haze is quite easily visible to the right of the “Trifid”. The best way to see M20 was at 100X and 200X magnification and using the UHC filter, although the wide angle view with the 31mm Nagler did give a nice contrasty view of the nebula floating in space, with the wide angle, it was like looking out of a space craft port hole.
Comparing the view of the Trifid Nebula to how I saw it from a dark location through the 8", it looked about the same, so not bad for seeing the same view but from a much brighter and worse seeing condition sky.
Globular (M4): M4 is quite a small Globular cluster in Scorpius near Antares on the eastern side. This globular needed 200X magnification to resolve its core into granulated stars.
Globular (M5): Another Globular Cluster picked from the SW14 deep sky tour hand controller. This Globular is quite bright and looks quite nice in the eyepiece, definitely a considerable amount brighter than, for example, M4 and M80.
This Globular looks tightly packed at the core, where the granulation is visible at 100X very easily, and less dense sprinkling of stars at the edges.
This Globular Cluster is a worthwhile object to observe during a night of observation.
Wild Duck Cluster: This cluster is something different, heaps of stars quite tightly packed, looking almost like fireflies rather than wild ducks. There was the shimmer visible through it which gave it a “being alive effect", it is a good sight at 50X and 100X magnifications. As most objects, this one would really benefit from a dark transparent sky to have the "fireflies" as sharp pin points of light since tonight it sort of looked soft focused.
Globular (M2): Another small globular needing 200X to resolve stars at the core, this one seemed tightly packed. I just had a quick look and moved on. Maybe I should have studied it a bit longer but initially it resembled M4 and other small globulars.
Globular (M22): M22 is a bright Globular Cluster in Sagittarius. The Sagittarius and Scorpio constellations have, by the look of it, a lot of different types of Globular Clusters.
M22 is almost as impressive as the Pavo Globular cluster, it is almost as bright and big as the one in Pavo which places it in close position four of my favorite globulars to date.
At 100X I saw a dense core with less dense randomly sprinkled brighter stars at the outer edges.
Definitely worth a visit.
Globular (M28): M28 is another smallish Globular, not too dim, and a bit bigger than and not as faint as M4. This Globular looks good at 200X.
Southern Pinwheel Galaxy (M83): Tonight the view of the galaxy was disappointing at best, all that was visible tonight was the glow of the core, no spiral arms were visible at all at any magnification, 50X-200X. Not even the “S” shape coming through, simply the sky was not transparent enough and I guess it didn't help for it to be getting quite low toward the west.
Saturn Nebula: As the last time I looked at this planetary Nebula, it was a fuzzy greenish oval, looking almost as if it's always out of focus, only knowing I was focused by the stars near it. 300X needed to see a decent size, but still looking like a featureless oval that is poorly focused, UHC filter didn't help either.
Looking at the Hubble image is obvious why it is looking out of focus. It is a planetary nebula within a fainter more diffuse nebula with a bar structure flowing through it, so at a lower resolution, fainter monochromatic view, the more diffuse nebula flows into the central nebula resulting with a fuzz oval view.
Helix Nebula: The "Eye of God" initially looked like a smokey oval which was quite hard to see with no central star and initially only showed dimmer fuzzy center.
I stopped observing at about 23:00 because I wanted to see the Helix Nebula higher up in the sky so I decided to comeback to the Helix later.
I left the scope tracking on the Helix Nebula for almost 2 hours, and returning at 01:30 when it was much higher in the sky, I was pleasantly surprised that it was still in the FOV... not center any more but still in the 100X magnified Ethos eyepiece FOV.
Using the UHC filter the smokey ring was much easier to see than before, when it was lower in the eastern horizon. The smoke ring was defined with a dimmer center, the top and bottom parts of the ring were noticeably brighter with the central neutron star visible when using averted vision.
Some of the main stars that I remember in the image I took a while ago were also visible there around the smoke ring. The view in the 8" did not reveal as much detail even though I tried to observe it in a darker sky condition. Not bad for what I saw during a milky bright sky. I was under the impression that there was little or no difference between the 14" and the 8", but after seeing the difference in the Helix Nebula, perhaps I was wrong, and just have the wrong idea of what 3X light gathering power really means.
I wonder how it will look under a dark, crystal clear sky.
The view without the UHC filter made the central neutron star just barely visible with direct vision, along with the stars around the nebula but the nebula was a lot less obvious, still hinted at some nebulosity, but the structure was not discernible.
Under a darker sky I'm sure the view will be staggering.
M80: Much like M4 except a little bit fainter. M80 is near Antares on the other, western side. This Globular Cluster needed 200X to resolve the sprinkling of stars that seem to be more sparse at the edges.
M9: This is a small and faint Globular cluster that needed to be magnified 200X to see any granulation through it but it is still small when comparing to The Pavo Globular Cluster, M22 or even M4 or M80.
300X was needed to see it at a decent scale where it was still a fair bit fainter than the other globs I observed tonight but at this power it had quite obvious star separation visible in the form of granulation all the way into the core.
Neptune: At 150X Neptune was a tiny, pale blue disc not much bigger than the bright stars near it.
There is no hope to see any detail in the atmosphere of Neptune so any more magnification is pointless, plus the atmospheric conditions wouldn't allow for it anyway, but it was a tighter point of light than last time I targeted it. It also was a lot higher in the sky.
Seeing was quite poor tonight coupled with a lot of obvious sky glow visible to a level where the sky looked milky when dark adapted, resulting in loss of contrast and transparency causing fuzzy views and lack of details. The poor transparency was particularly visible on the brighter nebulae such as M8. The poor seeing also made it impossible to tell whether tonights careful collimation helped the ability to get crisp detail at above 400X magnification.
As night went on, the condition improved slightly but still nowhere near the best seeing conditions which I experienced in May. The slight improvement in seeing conditions, along with being higher in the sky, might have been the reason for the increased details and features that I saw on the Helix Nebula after coming back to it 2 hours later.
Looking at the objects I bagged tonight, most of the them, by far, were Globular Clusters so I guess tonight was a "night of the Globular".
After not expecting too much due to the seeing and taking the lazy Deep-Sky Tour option tonight, I did get a few nice surprises, namely the Helix Nebula, a possible pillar of creation in the eagle and a few nice and bright Globular Clusters, few of which I saw for the first time.
I noticed Pegasus/Andromeda at 02:30 as I was packing up and so I tried to find M31 with the binoculars but it was too low in the north, in the direction of many street lights that washed any hint of it away... I guess I'm situated to far south.
If you read this novel of ramblings of a astro-nut to the end, thank you and congratulations.
Halloween Observation Night
Date: 31 October/ 01 November 2016 @ 22:30-01:00AEDT
Equipment: Celestron 8SE on CGEM, Televue 31mm Nagler Type-5, 17mm Ethos, 2X 2" Powermate, Astronomik UHC Filter
I finally had a clear moonless night of observation, it just happened to be on Halloween night. I was looking for a new spot in the mountains where I could setup and a couple of months ago I came across a nice little oval miles away from the city and light sources so I was hanging to check it out. When we arrived, there were people having a BBQ and playing tennis with all of the court lights on, this was a bit of a bummer but I figured that they won't be forever and eventually we'll have a clear night of viewing, they left just after 22:30. Once they left and lights were off we had some nice views of 47Tuc, Tarantula Nebula area, Orion Nebula, The Sculptor Galaxy, NGC362 Globular Cluster, The Helix Nebula, an Open cluster in the south near/around Theta Carnia, Uranus and Neptune.
47Tuc: The globular cluster clearly stood out with its millions of glistening stars becoming denser toward the core. As I was observing the cluster in the 17mm Ethos, a slow moving and bright satellite flew past it. Those views are an event that makes a already great view even better. The view of 47Tuc were all awesome using both 31mm Nagler and 17mm Ethos with and without the 2X powermate.
NGC362: This globular was a lot smaller and fainter than 47Tuc but still had a lot of individual stars all around it and individual stars visible within the core. Not as impressive as 47Tuc but still a nice view through the 17mm Ethos that's very easy to see with direct vision.
NGC 2070: The Tarantula Nebula was a very nice view in all powers. The loops around a obviously brighter tentacular center were faintly visible, especially when observing it using the averted method. I started the viewing using the 17mm ethos through which I saw a fair bit of detail on a quite big tarantula nebula in the eyepiece.
The surprising view was when I had a look at it through the 31mm T5 Nagler. The FOV was large enough and magnification low enough for being able to position the Tarantula in left lower with nebulosity amongst hundreds of stars to the right visible where a bit of the large Magellanic cloud was coming into the FOV. There was some fuzziness and nebulosity above it, I thought what a great view, this would make a great photo. The view of the tarantula system through the Nagler was amazing, I saw nebulosity, hundreds of stars and it was all easy to see.
M42/43/Running Man: Orion Nebula was a bit of a disappointment. Granted that I was waiting for the Orion nebula to come above the trees and it was not very high in the sky at the time, but I am comparing it to the view I had in the past. The shape was visible, with the trapezium clearly visible with the stars being very stable and sharp points of light, so I figured that the seeing was good, so why do I not see more detail in Orion Nebula? I saw way more nebula and detail in the past. I added the UHC filter in the eyepiece and sure it faded the stars but it did not bring out more detail like it did before, actually it made the view worse! Using both the Nagler and Ethos, in both magnifications the nebulosity was not as defined and clear as in the past but definitely there.
M43 was not as defined as I saw from the dam at the start of the year, back then the "comma" shape was clearly visible and even detail visible with in it, not tonight, I was struggling to see the comma shape.
The Running Man was nearly visible, I actually think that at times I saw the running man shape, about as good as I remember seeing it at the beginning of the year, so seeing was (most likely) good so why am I not seeing the nebula like before?
I started to investigate. First I checked to make sure that the corrector plate was not fogged over, it was not, that I removed the real cell filter in the back of the scope on the visual back thread, thinking that maybe it takes away from the view. When comparing with and without it, I saw no difference, even suspected the dew shield perhaps causing some kind of a slight blockage and compared with and with out it, no difference, finally I re-collimated the mirrors, they were slightly out, but after collimation it again made no difference. I put it down to a combination of Orion nebula being too low in the sky just above the trees and in the direction of the city. Here I'll mention that the sky did seem quite bright, I thought that maybe my eyes were dark adapted and it seemed like it but maybe not, more on this later with my experience when I was packing up for the night.
I guess I have no choice than to try again and see if a darker/more transparent sky will make a difference next observing session.
NGC253: The Sculptor Galaxy was relatively easy to see, whether inverted or direct vision I could see a brighter center in a squashed oval, cigar, shape. Occasionally I think I saw some darker "cracks" through the brighter core along with 3 to 5 faint stars glistening within the elongated shape. Sculptor is big in the FOV so I kept it on the 31mm Nagler, the Ethos did not make the view any better or easier to see. I could see the galaxy clearer the more I looked at it and feel like I didn't spend enough time looking at it.
NCG7293: The Helix Nebula was a faint but a big ghostly smoke ring in the 31mm Nagler. It is very faint but the smokey ring can be made out using averted vision, or slowly moving the view with the keypad set to "3". I could make out the central neutron star, very small and faint but definitely there. Next time I observe this object I'll have to try looking at it through various filters instead of just bare, maybe more will be visible.
Southern open star cluster: visible with eye as fuzzy patch closer to a dust cloud rather than stars but in binoculars and in the scope was visible as heaps of scattered stars, Looking at a star map it seems to be the cluster around Theta Carina. Looked like hundreds of pin point stars were spilled into the FOV. Quite a nice view, no nebulosity visible within its vicinity.
Uranus: It is a pale greenish tiny disc that's discernible from the stars around it due to its color and a little disc as opposed to a point of light, I saw no moons.
Neptune: Neptune was a pale tiny grey-blueish disc barely bigger then the two stars next to it. As with Uranus, I didn't spend much time on it since there's no hope of seeing any more detail.
As a last object due to its late rising this time of the year, I wanted to see the rosette but it wasn't above the trees by 01:00 when we left. Still I found it in the eyepiece and identified the 7 stars located in the center making a rhomboid shape. I read online that this nebula is one where a UHC filter really makes it stand out, so I had to try it.
The center stars were still behind tree tops and sad to say that with and without the UHC filter I did not spot any nebulosity. This object will have to wait a couple of months for a darker night and when it's higher in the sky.
The 31mm Nagler, 17mm ethos, 2" 2X Powermate and the Astronomik 2" UHC filter is all we took... Honestly you don't need any more than this to observe using a 8" SCT. This combination covered various magnifications and limited fumbling around in the dark for eyepieces or filters allowing more time at the eyepiece.
We had some great views tonight and I can't wait to be in a dark site when the seeing is even darker with less or no sky glow.
Surprisingly the Astronomik UHC made the views worse on all occasions. Not like the Lumicon that gave me the wow views on the past, unfortunately the Carina Nebula was below the horizon so I couldn't test on it, the Carina is really breathtaking through the Lumicon UHC. Next time I'm going to compare the Astronomik 2" to the Lumicon 1.25" which I didn't have with me, I'm hoping that it was just the seeing otherwise I'll eBay it and get the 2" Lumicon.
Another combination I want to try the 2" TVs with is through the f6.8 reducer.
It seemed like there was heaps of skyglow. We made sure that we were in total darkness, no lights except purely red lights. Yes lots of objects and stars were visible, more than from home but when we were packing up when I turned on the car head lights and we were hit by white light destroying our night adaptation. After we were packed up, I turned off the head lights and I looked up and to my surprise the sight was similar to "dark adapted" eyes!!! Perhaps it was a night of bad seeing after all, which would explain the lack of nebulosity and detail within. The skyglow was obviously quite severe and it wasn't the best I've seen in a dark site, but still an awesome night of observing, leaving me with a hunger for more.
Thanks for reading, clear skies,
Seasons greetings, all! HiloDon and I are at it again with another seasonal delight for our friends here at SGL! HiloDon provided the stellar images and I created the musical landscape and produced the video. There's a little surprise near the end! Hope you enjoy!
For all who observe, have a Merry Christmas and Happy New Year!
This is a reprocessed image of the Helix Nebula Data I captured and posted previously.
This image has been exposed across 4 nights, 2 nights through a HAlpha filter and 2 nights through a OIII filter using my modded 40D.
Helix nebula is fainter than I thought it was going to be, I had to image it at ISO800 30 minute HAlpha subs and ISO1250 OIII 30 minute subs, total of 8 hours through each through my 8" SCT at F10.
I just wish I captured more clearly the comet shock waves visible in the Hubble images... But overall I'm happy with how it came out... As always there is room for improvement...