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Showing content with the highest reputation on 28/03/21 in all areas

  1. I'd missed out on the clear skies earlier in the week having been slightly flattened for 48 hours or so by my first Covid jab - glad to feel it was working though and oddly relieved considering I hadn't thought myself unduly worried about getting the virus. When SGL-ers were putting out the big guns on the moon this week though I hadn't felt much like standing in a field at midnight, consequently I was particularly keen to get out Friday for some observing. Last full moon I'd canvassed the hive-mind on here and picked up a fantastic moonwashed target list and enjoyed a couple of fabulous nights centred on Double Stars. I set out armed with a hit list of Doubles, mainly in Bootes and a plan to have a look at Porrima in Virgo and Alpha Herculi. The wind was stronger and a lot colder than I'd bargained for and at midnight-thirty or so there was much more cloud around than the forecast window on both CO and Met Office cloud cover. Moonlight was casting shadows & playing on high cloud leaving only mag 3+ or so stars visible naked eye. My mid rugby-pitch spot took on an unexpected arctic tundra feel... Aligned on Vega and Arcturus, noting that both looked a bit blobby in the Mak 127 & Baader Zoom. Epsilon Bootes - had thought to start the evening with what looked on paper like a gem and doable split of 2.9 arc seconds - but no, the wind vibration was too much - I couldn't tell what was what. Porrima - definitely split this at around 150x but mushy view - the magnification required wasn't really supported by the seeing & flitting cloud. I'll count it as split but need to revisit to get that nice crisp view & "Oooh" moment! At this point I gave up on the list, chilled out, stuck some music on and trained both the Mak 127 and ST80 (on a new-to-me EBay Manfrotto 55 & ball head) on the moon, well if you can't beat them... Cloud was by now thickening and I watched it scudding past the almost full lunar disc in wide-field in the ST80 at 17x, quite beautiful. I noted a really bright, white spot both in the ST80 & naked eye in the NW quadrant and in a brief gap in the cloud trained the Mak to that area and cranked up the magnification. Finally got my "ooh" moment for the night looking at what I later checked as Aristarchus and Herodotus craters - the first so bright and the second contrastingly shadowed. I "flew" across to the terminator and down to the pole vowing to spend more time familiarising myself with lunar geography. I felt the first raindrop and, based on the lessons of a lifetime of hill-walking, figured that as raindrops rarely travel alone it was time to rapidly get some lens caps on and beat a retreat. It was raining steadily & properly cold as I trudged back but I'd renewed my wonder at the moon & really enjoyed a new mount for the ST80. Spent a nice hour thawing out with a whisky and map of the moon.
    14 points
  2. Back in October I found this faint object by surfing in Taurus on Aladin Sky Atlas and did not recognize it until I started processing and suddenly realized I was looking at the Baby Eagle. Seeing was not the best and processing was quite challenging. I have now had the EZ star reduction script in PI to have a go at it. It really helped to suppress the star field to a level that lets the faint nebulosity shine. Data gathered with a RASA 8 and ASI2600MC, 73 x 4 min at gain 100. I like they way this combo can bring out colour and light in objects that often look rather dull.
    11 points
  3. Taken on 6th March, 72 minutes with the Samyang 135mm f2 and Canon 6D (cropped).
    11 points
  4. Here it is. The mighty, mighty VX16 with ultra grade 1/10pv mirrors, 1600mm FL, fully flocked tube, recent upgrade to Starlight Feathertouch dual speed focuser with 16" curve base - low profile with 67mm travel, dob base with four bespoke handles fitted, teflon friction brake, hand truck with pneumatic tyres, Bob's Knobs on secondary, Vixen finder base and elastic dew caps at both end. The mirrors are in absolutely stunning condition and give great views, with no sleeks and hardly a trace of dust even shining lights on it. I specified the focuser very carefully and it brings all of my Ethos EPs to focus with a Parracor. I found it a lot easier to collimate than my new CC8 (I prefer laser collimators on dobs). I had no problem moving it around on the hand truck on my own and I'm only 5'9". It's not that heavy thanks to the aluminium tube. This scope is absolutely epic and I am very reluctant to part with it. I had great views in it from my back garden in Surrey but I've moved house and the room that this scope lives in needs to be refurbished and this scope needs to go somewhere else. There are minor cosmetic marks on the tube mostly from where the ring felt rubs on it but nothing serious and of course nothing that affects the views. New this scope is £4300 plus the Feathertouch cost at least £500 to import from Starlight Instruments, plus other bits. £1,625 I suspect couriers aren't going to take this and I have a small-ish sports car these days so I think buyer will need to collect from SW19 5P though this of course can be organised contact free and safe. I am very close to the A3 so easy access by car. Any other ideas for transport welcome.
    10 points
  5. I managed to image the nova last night so here's a blink with all of my original data from 05/12/2020 and last night, 28/03/2021. Nova V1405 in Cassiopeia. My previous image, taken 12/05/2020 was 5400 seconds of Ha data - 30x 180second exposures. It was taken during a new moon from a dark location. I knew last night's image would not be a perfect match since it was taken from a Bortle 6 location with a nearly full moon, but it did allow me the opportunity to match the framing and exposure time enough that it makes the nova really stand out in this blink.
    7 points
  6. Landscape astrophotography is something I’m interested in getting into more. There were some faint Aurora recently so I decided to give it a go. This is a foreground stack of 3x180sec on foreground and 1x30sec for sky, Nikon D600 and Samyang 14mm. A half critical eye will show my blending needs work and of course the sky is quite noisy since it’s only one frame at fairly high ISO. Hopefully it’s still semi pleasing to the eye
    7 points
  7. I have been a Ha solar observer for over 20 years. I began with a Coronado Helios1 70mm telescope, bought used for £2000, it was the one originally used for Coronado's publicity photos. When the PST arrived on the scene I was amazed to find that a good one gave very similar performance at the then price of £499. I purchased a used one and subsequently another to make a PST binoscope which gave wonderful results. The cost of larger apertures then, as now, gave me no option but to make my own so I joined the early pioneers of PST modding and have made more than 20 in the 100 mm- 150 mm range. My current PST (Peter's Solar Telescope) is a 150mm F10 optimised for high resolution, high magnification binoviewing. I have no interest in imaging or full disc viewing, I have a 60mm for the latter if needed. I have no extra input to the X versus Y "debate", I have seen excellent and disappointing versions of all makes.
    5 points
  8. You talked about corvid being a reason for the price rises, rather than covid. Just a little tease Political discussions always get out of hand on forums eventually due to the wide range of opinions and the polarised nature of thoughts around contentious issues. That’s why we have a no politics rule on the forum; we are first and foremost and astronomy forum, that’s what conversation should focus on. There is no harm in saying, for example, ‘price rises are happening due to Brexit, Covid, trade wars etc’, but please do not discuss the merits of political decisions and how we got here. We should just discuss the impact it is having on us, not whether it was a good idea or say ‘xxxxxx politician is a numpty because ........’! Plenty of other places to discuss politics, just not here please. Hope that’s clear.
    5 points
  9. Here's my blink. My original image blinked with the image from Sky & Telescope showing the position of the nova. I'm hoping to capture it later tonight.
    5 points
  10. As the Title states I'm entering a few images to this competition https://www.dias.ie/2020/12/16/reach-for-the-stars-diass-astrophotography-competition/ and I can't decide on the final image to enter. I've narrowed it down to the images below and would love to get opinions. Thanks in advance for any feedback, and don't forget to vote. CS to all, Richard.
    4 points
  11. After an initial comparison with it's predecessor the ASI 290mc (Not the 1290 as I keep calling it), I go for first light using the ASI462mc and the Heritage 150p. Trying to capture the ISS during 90% cloud with no experience turned out to be all too much, but I did see an interesting appearance on the Moon thanks to how the sun was shining on a crater!
    4 points
  12. Hi everyone, Sorry, it's been ages since I've posted anything here, as my sketches tend to be a bit rough around the edges so I'm never really sure whether to post here, or on the observing report forum and just attach my very rough sketches there. Anyway, I was just pleased to: firstly get out with the scope just recently, and secondly, to make out some of the fainter stars in the trapezium which had eluded me before. I then noticed the lovely grouping of stars near to the Orion Nebula while i was taking a wide-angled view of it. So I also took a closer look at the stars there and found out that they were Hatysa, Struve 745 and Struve 747. (Thanks to "Turn Left at Orion"). There's some more faint stars around the trapezium so I'd like to have another look around there when I can and see if i can make out any of the others. So much to see in Orion, and great to have a couple of clear nights! Cheers all.
    4 points
  13. Hello First picture of this lunation. a lot of turbulence with very short moments visible details. So I often work in infrared 807 and 742. the same image in two resolutions 100% for 4K and 75% for small screens. Clear skies. Luc 75% http://www.astrosurf.com/uploads/monthly_2021_03/605e4673705c7_AUSUDDECLAVIUS2403202121H28NEWTON625MMBARLOW4FILTREIR807QHY5III178M75LUCCATHALA.jpg.1d6ce1c17af808dc6d26cabbc7c8b61c.jpg 100% http://www.astrosurf.com/uploads/monthly_2021_03/605e468c25a24_AUSUDDECLAVIUS2403202121H28NEWTON625MMBARLOW4FILTREIR807QHY5III178M100LUCCATHALA.jpg.57470b073986287f9b62ed81e2e161b5.jpg
    4 points
  14. Blast from the past. 2 years ago, when I got the Samyang 135mm f2 lens, I couldn't wait for the winter to come so I can shoot Orion widefield. Well I did shoot it but I forgot about the data and 2 days ago when I decided to redo some of my 135mm work I stumbled upon this untouched data and I went to work Details and full resolution on my astrobin account https://www.astrobin.com/5i2906/?nc=user Emil
    4 points
  15. Today we released version 0.21.0 of Stellarium. The major changes of this version: - We have finally completed our work on accurate planet axes, including Lunar libration - Visualisation of Earth shadow for Lunar eclipses - Better texture for the Lunar surface - Added the latest algorithms for planet magnitudes - Enhanced Calendars plugin - Replaced "arabic" by more accurate "al-Sufi" skyculture - Planets are now scalable and Solar glare switchable for didactic applications We have also published a scientific paper about the application of Stellarium in cultural astronomy: https://doi.org/10.1558/jsa.17822 Download binary packages for Windows, Mac and Linux you may here: https://github.com/Stellarium/stellarium/releases/tag/v0.21.0 Full list of changes: - Added accurate planet axis orientation and rotation (GH: #502, #151): - Added lunar libration (GH: #877) - Added lines for the Invariable Plane and Projected Solar Equator (GH: #358) - Added solar altitude to planetary feature nomenclature - Added describe planetary coordinates and changes in the nomenclature display into Stellarium User Guide - Added new language: Spanish (Latin America) - Added ability to scaling of Sun and planets (GH: #1263) - Added new magnitude algorithms for planets from Mallama&Hilton 2018 (GH: #574) - Added Earth shadow circles for topocentric observer (GH: #430) - Added new 4k texture for the Moon (required re-balancing planet shader brightness) - Added lower limit for aFOV parameter of ocular in the GUI to avoid input wrong data (GH: #1487) - Added visibility of an antisolar point for other planets (GH: #1481) - Added ability to get all designations of DSO in scripts (GH: #1477) - Added ability to show hourly motion in decimal degrees (GH: #1478) - Added more cardinal points (GH: #1522, #1529) - Added ability to switching off drawing of Solar glare (GH: #1538) - Added a new sky culture based on Al-Sufi "Book of Fixed Stars" written ~ 964 AD (GH: #1548) - Added Old Hindu calendars - Added Islamic (algorithmic) and Hebrew calendar. - Added French Revolution calendar (arithmetic version) - Added Persian (arithmetic) calendar - Added button to set standard atmosphere - Added ability to translation/transliteration of Roman (latin) terms (GH: #1511) - Added ability to use UTC time when navigational stars are displayed (GH: #1416) - Added acknowledgment section into Help/About window (GH: #1568) - Added cosmetic fix for radio communication data: no need extra precision to show data in Satellites plugin - Fixed compatibility of ToneReproducer shader with GLES (GH: #1549, #1550) - Fixed retranslation of calendars (GH: #1545) - Fixed vertical position of calendar info panel - Fixed height-dependent twinkle for star-like objects (GH: #1542) - Fixed capturing a screenshots under macOS High Sierra and later (GH: #102) - Fixed documentation for API - Fixed display the extincted magnitudes for all objects - Fixed reading textures (GH: #1547) - Fixed alignment of an intercardinal direction markers (GH: #1552) - Fixed work of multisampling mode when in Spout isn't used (GH: #1537) - Fixed visualization zodiacal light at low Bortle values (GH: #1489, #1510) - Fixed the drawing a degrees on compass on HiDPI devices - Fixed search short phrases (GH: #1528) - Fixed orientation of Jupiter, Uranus and Venus (GH: #357) - Fixed inexact rotation of Moon (GH: #347) - Fixed wrong rendering of Jupiter (GH: #1261) - Fixed incorrect moon terminator (GH: #973) - Fixed a skybox.ssc script (GH: #1461) - Fixed crash when trails are enabled (GH: #1471) - Fixed crash when choosing Zero Horizon landscape (GH: #1466) - Fixed displaying labels of coordinate grids on HiDPI devices (GH: #1445) - Fixed a labeling hour angles (GH: #1457) - Fixed API docs - Fixed styles of QMessageBox and QColorDialog (GH: #1451) - Fixed WUI of Remote Control plugin - Fixed HiDPI issue for Observability plugin - Fixed the placement of cardinal marks when compass mark is enabled on the HiDPI devices - Fixed placement of the value of equation of time for HiDPI devices - Fixed crash at exit (GH: #1479) - Fixed work of Spout mode: inhibit multisampling when in Spout mode (GH: #1507) - Fixed DOI link for "Calendrical Calculations" (GH: #1562, #1566) - Fixed missing strings for translation (GH: #1562, #1566) - Fixed tooltips and placeholders (GH: #1562, #1566) - Fixed comments for translators (GH: #1562, #1566) - Fixed updating placement of calendars when visibility of calendars are changed (GH: #1567) - Fixed artifacts in the GUI when language is changed - Fixed images and typos in Stellarium User Guide - Fixed bibliography in Stellarium User Guide - Fixed the figure of Virgo constellation (GH: #1570) - Fixed stupid typos in satellites.json file - Fixed illumination during Lunar eclipse in Scenery 3D plugin (GH: #1506) - Fixed behavior "Clear" button in Script Console (GH: #1499) - Fixed lunar magnitude: try an accurate Lunar magnitude formula (GH: #1350) - Fixed lunar eclipses: redo the eclipse push effect for lunar eclipses - Fixed behavior of Bookmarks tool when pressed button "cancel" in import dialog (GH: #1497) - Fixed Mesa mode for Windows (GH: #1551) - Fixed multisampling on non-Windows systems (GH: #1553) - Fixed typos in Al-Sufi skyculture - Fixed bug for calculation the leap years: restore leap year rule in our astronomical year counting - Updated translations - Updated translations of landscapes descriptions - Updated translations of 3D sceneries descriptions - Updated translations of skycultures descriptions - Updated AstroCalc/Phenomena tool (GH: #1520) - Updated planetary features data - Updated building instructions for Windows (GH: #1444) - Updated core: slight restructuring of Planets, Comets, MinorPlanets, SolarSystem loader - Updated core: using data from WGCCRE reports 2009, 2015 and Explanatory Supplement to the AA 2013 (with error fixed by the 1992 ed.) for rotation elements - Updated core: keeps original Stellarium planet rotation model (undocumented) where new rotation elements are unavailable - Updated core: make StelToneReproducer's xyYToRGB.glsl core function reusable (GH: #1468) - Updated code of INDI client to version 1.8.5 - Updated code for building Stellarium without NLS and Scripting support - Updated GUI (GH: #1204) - Updated Satellites plugin - Updated default satellites database - Updated GUI of Navigational stars plugin - Updated default pulsars catalog - Updated description of supernovae plugin (GH: #500) - Updated description of calendars plugin in Stellarium User Guide - Removed proper name for NGC 2194 (GH: #1530) - Removed Arabic skyculture: Arabic SC was replaced by more accurate "al-Sufi" skyculture
    4 points
  16. Topics getting too heavy ! To summarise .. prices have gone up .. some have gone up too much in a short space of time ( no astronomy pun intended) . We all have a choice . Pay the money or not . There are deals out there , if you shop around and now is probably the best time to ONLY buy what you need rather than all you think want . ( I am guilty of buying , quite frankly stuff I don’t use ) . Also a very good time to look at your intended “path “ in the hobby . I think higher costs , whilst unsavoury for everyone can have a positive effect in valuing the equipment we already have and certainly making us think more carefully about future purchases . Not easy for new enthusiasts to get into an already expensive hobby ( yes it is !!!! Just because some people can afford top of the range equipment , there are most that enter the hobby with a predetermined budget ) , but , although I doubt prices will drop much ( why would they ? Companies are in it to make money , after all ) .. there will ALWAYS be a healthy second hand market .. maybe even more so as a lot of people entered into astronomy during the pandemic but have decided that they do not wish to pursue it anymore . Phew , that was my summary .. no politics , just a bit of a reality check ! By the way , I used to be able to buy a bag of chips for about 10p ! There , that’s inflation for you .. £2.50 now !!!
    4 points
  17. Hey After a 15 year hiatus I recently found my interest in astro photography again, when I saw that some people are now taking photos with a 3" refractor from their backyard in London, that almost look like stuff from my favourite Anglo Australian Telescope Book 20 years ago. I got the bug for astro-photography in the late 1990's - owed to a good part to that mentioned AAT Book "A View of the Universe"by David Malin. When my classmates asked my to buy prints of my very first astro-photo of comet Hale-Bopp and the local newspaper wanted to interview me about it, it seemed to be the path to fame and fortune . Over the course of the years it all got out of hand a bit and ended with a monster 15" f/4.6 LOMO Newton on a 200lbs ALT-7 GEM and a ton (literally) of concrete in my parents garden. Photography on actual film with frozen hyper sensitised stock and manual off axis guiding for hour long single exposures. And the result: (My image processing 'techniques' didn't really help either - haha) By the time, digital consumer cameras became relevant, I had finished school and university and it was time to get to work for a living instead of saving for nerdy hobbies. So I took a last shot at Orion with the Canon 20D and trucked all my equipment (safe the ton of concrete, which is still in my parents garden) to a new owner. You can tell, that my image processing had not improved much over those years - haha. Now I see pictures taken with a stock lens from a backyard in London that make me want to fade into the wallpaper when I think back at what I 'achieved' with almost £20k worth of equipment in a reasonably dark location. Of course my efforts were limited by my own abilities and I never got anywhere near the possible potential of that wonderful setup. I do wonder, what capable hands could do nowadays with that equipment! (and I am truly tempted to get my hands back on a little setup and try again myself - it seems like that pandemic might have brought back an entirely different bug for me) Have a lovely weekend
    3 points
  18. Without wishing to hijack your thread too much more Nicola, I will just say (show) that once you do get these fully setup, they’re absolutely lovely and a joy to use Although I’ve only had an hour on the moon with mine, I can say that this FC-76DCU is going to get a lot of use as my main grab and go scope now Just need some clear skies again
    3 points
  19. That is a great scope, I've had a VX14 (previously Faulksy's) for some time now and I still don't feel like there's anything else out there I would change it for. Good luck with the sale.
    3 points
  20. Yuck, the F word!!! I stay clear of it, much prefer the company on here
    3 points
  21. The moon was too bright last night for any photogenic galaxy imaging, so fired up by @Astro Waves recent topic on what is the furthest object you have imaged, I got two hours of luminance on APM 08279+5255, a Quasar in the constellation Lynx. It has an apparent magnitude of 15.2 so not a difficult object to image, and to look at it's nothing special, but some of the numbers associated with this object are just mind blowing: Luminosity of 10 14 to 1015 times the luminosity of the sun. The active galactic nucleus is powered by one of the largest known supermassive black holes, 10-23 billion solar masses. Using comparative spectral measurements, this galaxy has been determined to contain the largest mass of water in the known universe, 100 trillion times the mass of the Earth's combined oceans. This is evidence that water formed early in the life of the universe, the radiation was emitted only 1.6 billion years after the Big Bang. Oh, and it just happens to be 12.05 Gly (12050 000 000 light years) distant from us. Hopefully I have copied these numbers from Wikipedia correctly, thanks for looking.
    3 points
  22. The data for this image was captured back in September and despite my best efforts at the time the output was pretty poor. So much so that I did not bother to post here (I think!). I put it down to just very poor data. But six months of learning and reading made wonder if it may have been more down to processing - particularly pre processing. I had become aware that the 700d sometimes shows some amp glow at the edge and also learned about the potential problems of using bias frames and scaling of darks. It was 4 hours of 240s subs with the 80ED and the 700d with the L-enhance. So I went back to this and did a full re-pro from first principles, without bias and without scaling and with a more aggressive cull of poor subs.And this is what came out. Now, its still not fantastic but I do think it is significantly improved from the first two versions: here the original done in PS and this my attempt once I started using Pixinsight and clearly showing the amp glow problem So for me this has been quite instructive as it has shown me that it is easy - especially for beginners - to jump to the conclusion that your data is poor when the data may be usable if you take care in your processing.
    3 points
  23. Switch-mode supplies contain 2 capacitors, one from one mains terminal to output (positive) and likewise from the other mains terminal to output (negative). The idea is they feed interference away into the mains supply, reducing RF noise. The capacitors are low value, meaning there is no electrocution risk (see below though). There are three consequences, one being that the output "floats" at half mains voltage. Another is that a capacitor failure can place mains voltage on the output - which is why a "fail open-circuit" class of capacitor is supposed to be used. These cost more, so you may find unsafe substitutes in dubious-source gear. The third consequence is in connecting other gear, with an earth and sensitive inputs, to the powered-up gear. It can and does destroy sensitive electronic input circuits as the capacitors discharge the "floating" voltage. Connect all gear first then apply mains, to avoid that risk. Usually not mentioned in the manual!
    3 points
  24. Well I found this very hard. I rarely do LRGB imaging because of LP so my processing is a bit sketchy. It has been great to look through all the images, especially @Goran combination of his top ten. This was my benchmark but I couldn't get close to replicating it. I have had a good few runs using all manner of PI techniques but in the end this was nearly all done in PS. I found the hardest part of the process was controlling those blue arms. The popped so readily with any sharpening/saturation processes and easily ended up dominating the image. I also found that it was very easy to lose the outer halo when increasing contrast. This has been my favourite processing challenge to date!
    3 points
  25. It has almost all been covered by previous posters. Like Peter, I am only interested in "close-ups." Except that I image. I used a very secondhand 6" f/8, internal 90mm D-ERF, PST etalon, original blocking filter and ASI120MC camera for a couple of years. Having had more fun, more often, than in all of 5 decades of the dark side, it was time to invest more heavily. Now I use a 180mm Baader D-ERF, iStar 6" f/10 H-alpha objective, PST etalon, Lunt BF1200S, FT2535 focuser and ASI174MM camera. I had to make my own main tube but everything else is just screwed together from standard parts. Since I practically live in my DIY 10' domed observatory during sunny days, the cost per minute has dropped like a stone. As already mentioned: You need good seeing for close-up images. Early morning or late afternoon are usually best. Though there is always a chance of lucky seeing. Your choice of H-a filter will decide the required focal ratio of the donor telescope. An off-the-shelf H-a scope will have made the choice for you. Buy from a reputable dealer. Or test a secondhand instrument yourself. Just because a seller belongs to a forum doesn't make them honest! Be VERY careful of buying anything on UK Buy-Sell without testing it personally!
    3 points
  26. Don't think crows have anything to do with it despite what your dealers are saying! (Sorry couldn't resist )
    3 points
  27. He's not saying that. He's saying that even if politics were a part of it, it would not be an allowable subject to discuss on here. You could probably say that new tariffs (Trump's 25% China trade war) or Brexit added X amount to the cost, but you couldn't discuss the merits or underlying reasons for either.
    3 points
  28. Hi all, Since my previous post getting started with a smartphone (through a 200PDS with HEQ5 pro), I've made several 'upgrades' & spent a lot of time 'trying' to improve processing skills etc, but have several questions on which would very much appreciate any advice / suggestions. Firstly I've progressed to a DSLR (after much deliberation I went with a Canon EOS800d) & so far very happy :-). Have also just completed the Rowan belt upgrade as I was getting elongated stars on quite a lot of frames. Have yet to try it out, what with the weather as it's been! I will attach the latest endevour (M101) (pre-belt mod, but having deleted the bad frames!). First question is, I'd like to repeat this image with an OHC filter, to try & pick up some of the nebulosity in the galaxy. I've found how to add separate image in another layer (in GIMP), but how about alignement? Is there any way of doing this automatically, or have to manually align? Since I would always need to remove the camera in this scenario (to fit the filter), I assume I would need to fully stack / pre-process the two sets separately & then 'merge' them together in GIMP. But the alignment is what's worrying me... 2nd question is really about processing flow. So thanks to previous advice from HTH, I'm using Siril to stack (lights, darks, biases, flats), I then get a bit lost as to what aspects it's best to edit in Siril & if it matters which order you do them in before exporting to GIMP. I'm typically doing photometric colour calibration, green noise remove, autostretch & background remove (which sometimes works well & sometimes doesn't, depending on the particular image!). Then export (was doing in 32bit floating point, but having now just added the pyastro plugins, I find I can only use them if I export as a 16bit!?). In Gimp, I haven't played much with pyastro yet, only just added, but typically I'm fighting with more background removal (gradients, fill with background colour etc etc (I find all the blur & despeckle techniques often mentioned don't work for me, always end up removing lots of data from the image), to be honest I've found that most attempts to get rid of the noise result in loss if image data!) & maybe some saturation & the basic contrast etc. Actually, this particular M101 image didn't need much processing at all in GIMP, so I'm thinking the key is to getting more imaging time (signal) & hopefully minimise noise to start with! I'm using ISO400 which seems good for the 800d & 3min exposures on this one. Previous targets were shorter exposure (various ISO's) & I don't think I was getting enough signal over the noise... Anyway, so really just some advice please on the best process flow with these two software packages & any other suggestions! Many thanks, Rob
    2 points
  29. Dear all, tonight the waxing gibbous moon stood very high in the sky. I was looking for the Golden Handle but it was just visible in the beginning of its appearance. Just the first summits were visible. In addition I pretty much enjoyed the ridges on the floor of Sinus Iridum. Here you are: Telescope: Martini 10" f/5 truss-tube Dobsonian Eyepiece: ExploreScientific 6.7mm/82° Date & Time: March 23rd, 2021 / 2030-2130 CET Location: home, Dusseldorf region, Germany Technique: Koh-i-Noor chalk, extra charcoal and whitecoal pens and pieces on black Hahnemühle Ingres mould-made pastel paper Size: 24x24cm Clear skies! Achim
    2 points
  30. Last night i was able to get another go at the nova in Cassiopeia. 1st pic is 2x180s with my ODK12 and A A ProTec294c,2nd pic is 1x180s through my Star71mm and Zwo 1600mc-c.. Bob
    2 points
  31. Asteroid 9 Metis currently rises in the early evening at magnitude +9.6. It will appear within Virgo in opposition to the Sun on 2021 APR 04 at magnitude +9.5, and near the bright star Spica in August. Metis is possibly the core of a larger destroyed asteroid. It was discovered in 1848, and has a mean diameter of 190 km. Photos and descriptions of Metis would be welcome additions to this thread.
    2 points
  32. @paul mc c @masjstovel I screwed off the dome part of the camera housing, and found that the lens was loose on the camera, just a 1/16 of turn. This had caused the vignetting. The only thing I did was turn on the heater between the above photos, but that looks like it was enough to cause it to loosen. I have noticed that my camera temp is 33 deg C now whereas before it was 10 degrees or less. The heater is 2.8W and it says to run on full power. Ive attached a new photo from a few minutes ago. Thank you both for your input.
    2 points
  33. Seeing one of the last ever Shuttle launches back in 2010 was incredible, the sound, while obviously nothing like a Saturn V was something that will live with me forever, crackling roaring all mixed together. Was fortunate enough to visit Florida again a couple of years back and see the shuttle we saw launch (Atlantis) now in its own amazing visitor center at KSC. I spent well over am hour just walking around it soaking it all up. Also, when I was 10 years old back in 1981 I went to an airshow at the then RAF Finningley. Something on the flying program caught my attention immediately with the title "Vulcan scramble". Turned out it was 5x Vulcans taking off forming up and displaying. Utterly amazing sound and spectacle. Still give me goosebumps 40 years later.
    2 points
  34. Thanks Simon, that was actually a first light image with my Takahashi Epsilon 160ed. Camera was Asi2600mc. 2 hours 60 second subs.
    2 points
  35. It depends on the paper size you print the charts on (it's a vector PDF so you can pretty much choose any paper size). The Deep-sky Watch atlas has a declination grid of 5 degrees, if you measure the distance between two grid lines you can calculate the size of the Telrad circles (they are 4, 2 and 0.5 degrees).
    2 points
  36. Take the f/ratio of your scope and multiply by 2.5. That will be the highest power, shortest focal length, eyepiece to use with nebula filters in your scope. Multiply the f/ratio by 7. That will be the lowest power, longest focal length, eyepiece to use with nebula filters. On an f/5 scope, for example, that would be eyepieces from 35mm down to 12.5mm. Generally, the lower power end of that range will be better than the upper end of that range, simply because that will yield a brighter image (albeit smaller). Why such low powers? Nebula filters work by dimming the background sky about 2.5 to 3 magnitudes while only dimming the nebula 0.05-0.1 magnitude. As you raise the power, the background in the eyepiece gets dimmer anyway. By the time the background is already quite dark, the efficacy of dimming the background further is significantly reduced. Then the 0.05-0.1 magnitude dimming of the nebula starts becoming more important. So above a certain point, the nebula filter just isn't helpful any more, and that occurs around a 2.5mm exit pupil (about 10x/inch of aperture).
    2 points
  37. I've read that too, but it has left me wondering whether this just applies to the mono version. I don't see how that can be compatible with a Bayer array of the OSC version. Perhaps a 294MC user can confirm? DOH! Why didn't I read your reply properly . Ian
    2 points
  38. Most if not all switch mode power supplies these days have no earth so the 0V output pin will be at around 70V or more, I have never understood why this is deemed safe by regulations. The best fix is to run a "safety" earth directly to the mount and any other metal parts. Alan
    2 points
  39. Summer is a marvellous time for astronomy, even from the UK. Yes, it doesn’t get dark completely, but that applies to most of us all year round due to light pollution. There is nothing like standing under the summer milkyway without freezing temperatures. So many clusters and bright nebulae in Cygnus, Lyra et al. On top of that, the gas giants will be on show, albeit low above the horizon, but hey - seeing Jupiter while in t-shirt is not bad at all, even if it’s a bit washed out (Jupiter - not the t-shirt)... I am looking forward to those nights already! Frank
    2 points
  40. The poor sods they have years of watching ahead of them - mercy, Jim
    2 points
  41. 2 points
  42. Sound like a good session. I always keep an eye on the radar. You can predict most showers quite accurately as well as persistent rain.
    2 points
  43. The advantage to modding an existing frac is you can use two larger external etalons, which normally offer more uniform contrast across the fov, compared to smaller internal etalons, which most solar scopes are built around (producing a ‘sweet spot’ rather than more even disc detail). Catch number 1 is they are more expensive. Quite a lot of Lunt scopes combine a small internal etalon with a larger external one - these can be excellent. Then obviously, more aperture reveals more detail, and allows you to retain sharpness at higher powers. For the money you’re investing, you should be looking at 70mm-100mm double stack, or LS130 single stack. The new Lunt range is modular, so you also get an ED night scope as part of the package. Catch number 2 is that all etalons are unique and variable, so there will always be exceptions to any rule - both nice exceptions and not so nice ones. I’ve seen 60mm single stack scopes that knock your block off with fine detail, and double stacked scopes of 90/100mm that have left their owners disappointed. But 99% of the time double stacking transforms surface detail and comes highly recommended. The third option is a rear mounted etalon (Daystar, Solar Spectrum), which can be used with any parent refractor, but these come with high power barlows to work at around F/30, so are mostly used for close up views, and require v good seeing to strut their stuff. They also require heating for 10 minutes before they’re on band, so can’t really be described as ‘grab and go’. I say this all the time but it bears repeating, all manufacturers of commercial solar etalons produce poor examples. Some more than others. So do your research - Solarchat and Cloudy Nights are particularly useful forums. If you are not able to test the product out first, make sure you buy from a reputable dealer who will take back substandard filters. Hopefully then you’ll end up with a scope that will provide you with decades of enjoyment. There’s nothing in the night sky that in my view compares with the sun in hydrogen alpha - watching our own star changing every day never loses its appeal.
    2 points
  44. Seeing only fair to marginal, but there were enough sharp moments to get decent resolution at prime with my new 140. Can hardly wait to push this baby with good seeing! (I did try a couple clips with a 1.5X barlow, but posted results underwhelming.) Please view the disc at full size! Lots of tiny details to be seen. :))) Here was my attempt at F10.5 (ASI290mm, 1.5X barlow and 685nm - best 500of10000)). I think perhaps there is just as much detail in the above image shot at prime with 183mm. Seeing did not quite support. Clear skies! Thanks for looking! Mike
    2 points
  45. Edit... I've added the moon image taken at dusk with slight high cloud at the time giving the moon a lovely glow, then images of M35, and M47 & 46 NGC 2423 only 5 subs no calibration files as I was just trying it out. I've a batinov mask on order for the scope now so focus will be sharper.
    2 points
  46. My grown kids don't watch TV except to stream Netflix and such. They don't watch the news because it makes them upset. Better to be uninformed and happy than informed and unhappy is their mantra I guess.
    2 points
  47. Hi all, Here's another attempt I made of the beautiful Clavius Crater. Still not quite there. It's the beautiful curve of the craters on the crater floor that make Clavius so beautiful and I keep not quite getting that, but I think this is my closest yet! . . . . next time I'll crack it, next time!
    2 points
  48. KONUS PERSEO after 35 years At the age of about 12, my mother and my uncles gave me my first REAL telescope. A great little giant who opened the windows to the Universe for me. Made in Japan, today I was able to partially restore it. Needs an intervention to the lenses that I have to collimate, since as a boy I disassembled it several times to clean it with ethyl alcohol Tonight, the sky suddenly opened up in the clouds, giving me an observation window with both the Baby-Mu and the little PERSEO. I observed the moon through an Adriano Lolli COMA adapter, which adapts the 1.25 "eyepieces to 0.96" of the original focuser of the "ancient" sacred relic. With a 25 mm Ploss Televue, despite a slight chromatism (surprisingly most of which deriving from a not perfect colimation) the little moon was greatly engraved. Beautiful. rich in detail. I also used an FF 12 mm eyepiece, which denoted a greater chromatism (but always very acceptable) and finally I dared with the supreme Abbe MC 6mm Takahashi, which still returned a usable image, with only a very slight graininess of the details and a coma on the peaks of the craters. I started crying reliving those nights over 35 years ago. A short walk among the stars, with very good focused stellar images, a short star test showing Airy discs (in extra) heavily etched in an image deformed by uncoupling. I'll take him to some expert soon for a comprehensive resuscitation. Then I wanted to dare, making the little old man savor the breeze of the modern era. Go of ASI224 with Astronomik ProPlanet 742 IR-pass filter and ASICAP. I shot some videos of which I quickly processed two, one for the ASi to rpimary little focus and the other through Barlow TeleVue 2x. Videos of a few frames (since we are still waiting for the frames from the east), processed with PIPP & Astrosurface. thanks Mom if you can hear me from up there 2021-03-22-1943_7-CapObj__100r_48T_326reg.tif 2021-03-22-1942_8-CapObj__100r_48T_262reg.tif 2021-03-22-1941_5-CapObj__100r_48T_675reg.tif 2021-03-22-1939_7-CapObj_pipp__100r_48T_366reg.tif
    2 points
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