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Everything posted by sergeC14

  1. Jessun, if this image was taken a the center of Lyon, then you have got nothing to kick yourself about. I do not really think 15 min subs will improve anything as sky background will drawn M51. Have you tried using a PL filter on the camera? That image is nice, you just need to correct color balance (way too much red) and not push the colors too much. As for noise, I don't really see it but try to do some darks, it really helps with keeping noise down. You can do them on a cloudy night, so as to keep them out of the critical path. Then, you can really stretch your image to the very bottom without having noise coming up (just background sky) to reveal more details. Rgds Serge
  2. just one word: whoaa! I guess that means you can now point anywhere in the sky and find a nebula... Serge
  3. M63 Stinging your eyes, or at least I hope so... For me M63 is THE MOST difficult target because it is so fine and detailed that seeing as to be near perfect. So; as you may have noticed from the Hickson serie, seeing here was quite good, so I decided to have yet another shot! M63 is pityless with approximated guiding. Everything HAS to be perfect for it. Scope: C14 EdgeHD, aperture 356mm, Focal:3980mm, (optics Lambda= L/4.2 PTV and L/21.5 RMS) Camera: Atik 11000-CM OSC CCD Exposures: 15x600Sec Processing: DDP under maxim, Edge preserving smooth under PSP 7 Comments welcomed Serge
  4. Really, thank you all for your very kind comments! I primarily do images I am pleased with, but it is always satisfying when other astronomers like them too... Thx Again Serge
  5. Ncjunk, speaking of "game of soldiers", well, we frenchmen, once you get past the bravado, we still do aim to shoot! Rgds Serge
  6. Ainsley, Hickson 44 is "only" 60 millions light years away. It's practically next door... Thank you all for your very kind comments. I also did Hickson 57 but it is less impressive by nature. May be I'll post it as well. Rgds Serge
  7. Quatermass, that's a nice image you got here, but Raw files are a prerequisite for DSLR as you know. Also, for this kind of work, you really have to dedicate an entire night to it, to record the faintest details. Nice work though, thx for sharing Serge
  8. ncjunk, 2800 mm? I wish!!! it's 3980 mm (F/D 11) so yes, the slightest P.E on the wormscrew, not being instantaniously corrected (guider using 4 sec exposures) will cause some very slight guiding error. Thank you all for your kind comments. Serge
  9. No darks? well, the result is awsome. mainbe just apply a despeckle noise reduction, and the image will be truly mind blowing. supeb Serge
  10. wel done olly, that's a superb image. So lively! serge
  11. hello everyone, I spent 36x100 sec subs (6 hours) imaging hickson 44 with the C14 EdgeHD with the fullframe Atik11000-CM OSC camera. I am quite pleased with the result as it is very deep: on the full sized image, one can see literally 1000's of faint galaxies in the background... I am not sure of limit magnitude, but I suspect it to be very high. full size here:http://www.sergepetiot.com/wp-content/gallery/various/hickson44.jpg Comments welcomed Rgds Serge
  12. very nice. it's perfect. really good, that's a difficult one. Serge
  13. a pixel becomes noisy 2 years later? It changes every week when you're imaging say 3 times a week... I hink it's natural radiation killing of pixels. Which is why I'll never buy a second hand camera. Serge
  14. Right! I am back from the French enemy line! so, And the answer is: 15 darks, signal to noise ratio is 3.87 20 darks, signal to noise ratio is 4.47 50 darks, signal to noise ratio is ... 7 So, the winner is... Earl! the more darks the better.... so, a good average would be 20 darks, regardless of the numbe of subs. So I have to look elsewhere for my noisy background. Rgds Serge
  15. Dear Me! I still don't really know how many darks to acquire... But 101 darks is way out of the question or I'll still be doing darks by next week with 600 Sec subs... Well, I'm just going to try to use the same number of dark as subs (oops, that's 36 +1!!!) and hope for the best. It's sure is starting to look like black mangic, even though we all do calibrations all the time! I think I'll go to the Astrosurf french forum and ask the question:). Most of them are a bunch of extremelly boring, ego-inflated, troskist guys (university types), but they are quite experts in this field. Once I get an answer, being a traitor to mother and country, I'll come bak and report on here.... I'll be right back Serge
  16. Thx you, that's very informative. I get alot of baseline "background" noise on my images (black background) whenever I try to bring out the faintest details (e.i faint galaxy arms), by having to stretch the lowest part of the histogram to the max. So, I was hoping that the number of darks I am using was the problem, but apparently, I already use plenty enough, usually around 15 regardless of the number of subs I have to calibrate... I guess I now have to look elsewhere, but, that being said, my sky is not extremelly dark, so maybe I need look no further... Regards Serge
  17. thx freddie. Ok, but would 20 be enough for 36 subs?. Also, one thing I have noticed is that the sensor changes with time, so darks library is only useful for a couple of weeks of intensive CCD use. Serge
  18. Hello Gents, I read somewhere on the web that using too few darks for calibration actually ADDED noise to the image... Is this true? I just spent 2 nights acquiring Hickson 44 and I have 36x10 min subs. How many darks should I use for calibation? It's just that usually I use less darks than subs and my background is pretty noisy. Thx Serge
  19. what a balcony! superb picture with loads of details. Well processed too... Serge
  20. well, my hat is off to you! managing to catch the horse red Halpha light with an unmoded DSLR is an impossible task, yet, you've managed it. Well done Serge
  21. splendid! so many details!!! Well done Serge
  22. That just shows you don't always need fancy CCDs and DSLRs are good enough for a fifth of the price! really nice picture of the rosette... Well done Serge
  23. themos, with the amount of subs you have, the information is there. Try to reprocess this image by bringing the low levels to the foreground. That can be a much better image, as it already shows everything M51 is about. Regards Serge
  24. Thanks, I try my hardest... Mind you, I don't lack targets with the C14. My main problem really is that I use an OSC camera hence processing is harder. Which is why I posted those raw images, so that I can get advice on post processing and et beter at it. I still have NGC4725 to process, but doctor house is on tonight on TV, here in France Serge
  25. Greg, that's a very nice picture! Can't see anything wong with it. Are you planning on doing color wih Halpha as luminance? That would be very nice. Serge
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