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StuartT

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Everything posted by StuartT

  1. Yep. 628 subs. I think they are 55MB each. But I don’t tend to keep them all once I’ve stacked them Three nights. Two hour sessions each night Not really. With SiriL it takes about 15 min. It’s a wonderful program
  2. Sorry, no. I meant it’s the first one I’m really pleased with. Poor English on my part. it’s actually my fourth DSO. I started out with astrophotography in august.
  3. Thanks. this was shot from my back garden in Oxford city. The L extreme filter cuts out all light pollution. my subs are 35sec. That is the longest I can go without guiding and still get round stars.
  4. thanks. Actually my son asked for this image so he can print it and display it in his house. I guess it's only fair, given I put up lots of his macaroni pictures in my house many years ago Dithering would require guiding AFAIK. I can't be bothered with that faff
  5. Cygnus Wall shot with my Esprit and an Optolong L Extreme dual band filter. 6h 5m of integration time. Stacked and processed in SiriL (I LOVE SiriL!!) 35 sec subs, unguided i should add, this is light frames only. I don’t shoot calibration frames any more.
  6. me too! I take it up to the top and still I have a mostly black image. Except the 'preview' box is ticked by default, so any changes I make in Asinh should be visible even without clicking 'apply'
  7. yes, I tried doing it a few times and maxing it out, but nothing happened. I think it very much depends on the type of image you have. But I am very happy with Siril so far. It made a lovely job of my first ever attempts at DSO imaging and with remarkably little effort or skill from me
  8. Thanks everyone. The photometric calibration is just wonderful! Works like a dream. I can't manage to get the asinh transformation to do anything useful tho. This is puzzling. In my hands, it just leaves the image totally dark. Fortunately the automatic gear button in the histogram tool seems to do a nice job so I just use that
  9. I just found this video which is perfect for a noob like me. He also explains a lot of really great Photoshop tricks! Thoroughly recommend this! I think I now prefer SiriL to Astropixel Processor. For one thing, it's MUCH faster!
  10. Hi Jim. Sorry you are having problems. I also have the EQ6R Pro and I think the main issue in getting polar aligned is that the bolts are pretty terrible! I use the SharpCap PA tool and after a bit of practice can get down to 15-20 arsecs. At my focal length, even an arcmin is plenty good enough. I actually put a little grease on the bolt threads which makes fine adjustment a little easier. The azimuth bolts are not too bad, but the altitude bolt is pretty terrible! But persevere. It can be done. Just go gently and don't adjust too much each time. I have my rig permanently outside (under a Telegizmos cover) which means I am staying more or less polar aligned the whole time and it only really needs a slight tweek every so often. I thoroughly recommend this, rather than setting up and taking down every session and having to polar align from scratch.
  11. I've only just discovered it and trying it out on some data. If anyone here has experience of it, or knows of any good tutorials, I'm all ears. Thanks
  12. aha! Of course! (I knew it was a dumb question!) Thanks
  13. Thanks so much for posting this. I think this is the first time I have actually understood this!
  14. Sorry if this is a really dumb question but surely a transit north is an altitude minimum, not maximum? This diagram is from Telescopius
  15. No. not used that one. But sadly the files are well and truly gone. I tried several tools. I've re-shot the sequence now. Thanks
  16. Well.. I think the effect of focal length kind of cancels out. Shorter FL may get you a less accurate PA, but then again they are less fussy about the tracking accuracy. I guess the question is how accurate do you really think you need to be? As I said I really don't see the point in trying to get down to a few arcsec for the sake of it, unless you are seeing mis-shapen stars
  17. thanks so much for this. I'd never heard of the hubble palette before, but google is my friend and I have now found a bunch of videos showing how to do that with an OSC. It seems that to really do the Hubble palette you need 3 channels of mono data with HSO filters, but it looks like there is a kind of 'fudge' for those of us with OSCs by using the 'selective colour' feature in Photoshop.
  18. this is very interesting. Thanks! No doubt somewhat has scripted a Photoshop plugin for this process too. I assume you worked off my FITS file? But I guess from a more philosophical point of view, it does make me wonder about the issue of 'realism' in astrophotography. To what extent does swapping out and replacing an entire colour channel really reflect any kind of reality? or it it more artwork? Though it would reasonably be argued that all the stuff we do in AP (even stretching) is 'unreal'... what does reality even mean in this context? (answers on a postcard )
  19. oh boy!! how did you find all that blue? I don't get that in Astro Pixel Processor...
  20. the image is now looking good because I used no calibration frames at all! Makes life a lot easier, for sure.
  21. so here is the final post-processed result. 2h 50m integration time and no calibration frames (lights only).
  22. not much different, if truth be told!
  23. Ok, so this is interesting. It's really looking like in my setup, stacking with no calibration frames is producing the best result! The first image is with darks, flats and flat darks. The second image is without any calibration frames. So just the lights stacked. Both are just as they come out of Astro Pixel Processor and before any post-processing. I'm also attaching the FITS for each one, in case any of you want to see what you can get out of them. Cygnus_Wall_with_L-extreme-RGB-session_1.fits Cygnus_Wall_with_L-Extreme-RGB-session_1_no calib frames.fits
  24. this is helpful, thanks. And you said (above) that bias frames are also not needed with this camera? Why is that?
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