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Littleguy80

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Littleguy80 last won the day on November 12 2019

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About Littleguy80

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  1. Haha I’m gonna put that down to autocorrect or perhaps I hadn’t quite woken up when I wrote that
  2. Etendue is interesting but I think we have to be careful when including the eyepiece. When comparing a Lunt XWA 9mm (100 degree) vs 9mm BGO (42 degree), the BGO goes deeper. The Lunt will have the higher HET value but the BGO is higher transmission/contrast.
  3. Agree with Gerry, superb image, Goran. Very well done. Beyond my observing and imaging skills!
  4. Thanks Andrew. Would that make a difference with the change in aperture? Wouldn't the eye's sensitivity be a constant, taking out things like dark adaption of course.
  5. Thanks Doug. Let me see if I#'m understanding it correctly. The surface brightness of each LED is the same but the cumulative effect leads to a bright torch. I guess this is where we get light acting as wave. The 10 LEDs add up to increase the amplitude of the light wave? The translation to the scope idea is that increasing aperture is like adding extra LEDs to the image because.....the resolution is increased? I think I get the idea with stars being point sources as you and Vlav both explained.
  6. Does increasing aperture, increase the image brightness for a fixed exit pupil? My feeling is that the image brightness remains constant through the fixed exit pupil and the change comes in image scale, which increases. If image scale is fixed then exit pupil increases with increased aperture and a brighter image is observed. Would be interested to hear people’s thoughts on whether my understanding is correct or not. This comes from a discussion on how aperture masks work and whether they lead to a reduction in the amount of light entering the telescope. Intuitively, it seems like the answer must be yes though I’ve been told this may not be correct.
  7. Thank you. Yes, there’s a section in IC1308 which looks very much like a butterfly. I have to admit I didn’t check if that was it’s official designation or not.
  8. Great report, Gerry. The Instellerum Deep Sky Guide has a number of sketches of planetary nebula seen at high powers in very large scopes. The details that can be seen are truly draw dropping. I do love planetary nebula
  9. Thanks Iain. Yep, there was a definite turning point where the dew became an issue. The dew heaters kept me going for awhile longer. I’ll have to look the dolphin up, I wonder whether that was the section of nebulosity that I haven’t identified. I forgot to mention in the report there I tried an H-Beta on the butterfly. I felt it lost a bit compared to the UHC. However, it’s a new target to me so there may have been some extra detail revealed that I missed. I’ll add the propellor to the list for next time.
  10. Thanks Gerry. Really appreciate the suggestions and tips. I love a challenge so Cehpheus it is lol I've read reports of people struggling to find the main stars of Cassiopeia because there are so many stars. Hard to imagine even with the 21+ SQM skies at my dark site.
  11. Inspired by reports from @scarp15 and @jetstream, I loaded up the car and headed out to the dark site with plans to explore nebula in Cygnus. I'd had a nice session Friday but transparency had been variable, limiting what could be seen. There wasn't much moisture in the air when I arrived. A quick look at Jupiter and Saturn to check all was working as expected. I spent a little time on the Helix nebula to get my nebula eyes on and then went straight up to Cygnus. My previous explorations of the Gamma Cygni region had been done with an OIII filter. This time I decided to switch to the Lumicon UHC filter. Starting at Sadr and moving straight to the Butterfly nebula and immediately I felt that the UHC was working better than the OIII. The nebula was brighter and seemed to be better defined. Nebulosity seemed to trail down from it so I followed this as far as I could. Then back up to the Butterfly and off in a different direction. Not really tracking where I was going, I spotted bright nebulosity and then realised it was the Crescent nebula. Easy to follow the full curve though I'm yet to catch the fine filaments within it. Not sure if this is a question of aperture, conditions or simply practise. Gerry, @jetstream, has posted on the Tulip nebula recently so this became my next target. Images of this nebula show it to be quite bright but I found this to be a tougher spot. Most of the observing so far had been done with my APM HDC 20mm but I now switched to the ES82 30mm to increase the exit pupil. This helped draw the Tulip out a little more. I tried both the UHC and OIII but notice much difference in the views between the two. Back to Sadr and I explorered further, passing the lovely open cluster NGC 6910. I hit upon another bright patch of IC1318, but where exactly was I? Lots of head scratching and looking at SkySafari and I finally decided I was somewhere around the star HD 228911, though looking at images this morning I'm not sure that's correct. It seemed to be quite a large extended patch of nebulosity. After this, I decided not to worry about identifying what I was seeing and happily roamed around looking for sections of the nebula. The Lumicon UHC proving to be an excellent tool for this. It was a really enjoyable way to observe, just looking around to see what caught my eye. I generally decide on a target and go off to find it so this made a refreshing change of pace. After this I toured around some favourites such as the Little Gem Nebula, Wild Ducks (M11), Barnard's E (B142/B142), Iris nebula, Merope nebula and Neptune with it's faint little moon, Triton. I returned to Cygnus before leaving to explore the NAN with the Lumicon UHC plus a couple planetary nebula, NGC7026 and NGC7027. It had gotten very damp by this point so I finished up with some views of Mars and then headed home happy.
  12. Sounds like you need an ADC I have a Contrast Booster which I’ve gotten into the habit of using on Mars. I quite like it. I should do a comparison with the Neodymium really. It’s just another tool in the box though. I think they can help with certain features but once you’ve got a bit of experience then you see it all anyway. The seeing, as you’ve described, is the key factor without going into collimation, cooling etc.
  13. Ace report, Iain. So glad you got out for a good session. Very inspiring for my session tonight. One thing that jumped out was the UHC on the NAN. I normally use an OIII. Will try the UHC to see if it draws out any new features.
  14. Great report, Gerry. I’m really looking forward to having a crack at the Butterfly neb and LBN 208! It’s ace to hear how you’re still finding new features in these targets.
  15. Thanks Dom. The Quintet needs good transparency, even under dark skies in my 10” dob. I suspect it’s a stretch in a 100mm frac but then I’m constantly surprised at what’s possible Triton is great to observe. Seeing a moon that far away is mind boggling. It’s another target that has taken years for me to get my observing skills good enough to see! Just gotta keep practicing!
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