Search found 13 matches

by ramdom
Mon Sep 14, 2020 7:09 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

Thanks Ivo. I have observed what you've observed - that the two thermal noise patterns match perfectly and the subtraction does appear to remove the thermal noise pattern but then when I do the full integration and stretch, the pattern/banding reappears and is hardest to deal with in the faintest ta...
by ramdom
Mon Sep 14, 2020 3:56 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

Here is my master dark where the large scale banding is present. Until we both agree on a different term for "unrelated calibrated problem" this is what I'm calling it. There are indeed three large bands. The small scale banding I've also defined. I don't see a problem once I've defined these two te...
by ramdom
Mon Sep 14, 2020 1:18 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

Also you wrote:

"....banding and an - unrelated - calibration problem, and stretching it shows that..."

What exactly is the "- unrelated - calibration problem"? I mean what are you referring to exactly in the final image?

--Ram
by ramdom
Mon Sep 14, 2020 1:16 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

I'm calling it (large scale) banding because there are three large bands I can see - not just because CBR removes it (though that is corroborative). I could call it "striping", "odd lighting", whatever. I think it's purely a semantic point - we have to call it something and like I said, there are th...
by ramdom
Sun Sep 13, 2020 12:29 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

Hi Ivo, that's what people who tried to help me before guessed: the problem was the flats (there was some thought it could be darks too). But they couldn't help me calibrate it out. Either my flats are being done incorrectly or there's something else. And my flats do remove the dust bunnies. But not...
by ramdom
Fri Sep 11, 2020 12:39 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

Hi Ivo, once again, I appreciate you taking the time to talk about these issues with me. Yes, that's my v0 file, i.e., the corresponding FITS. So this one to be precise (http://ram.org/images/space/downloads/ou4_O3.v0.fit). And the v0.1 is indeed the file with both CBR (CanonBandingReduction) and DB...
by ramdom
Wed Sep 09, 2020 5:52 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

I did however take a look at thread you pointed to on SGL and the images done using ST are amazing - it is good to know that can be accomplished. But the conditions for that set are amazing - they spent 100 hours on data collection and used 40 hours of it - throwing out 60 hours worth! That's not a ...
by ramdom
Wed Sep 09, 2020 5:39 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

Hi Ivo, since banding is the issue you're referring to, then it is indeed due to the large scale banding that is occurring and it was particularly bad for this target. You can see it quite clearly if you step back a bit, it's a dark/light/dark/light gradient---it's really bands, not a hole in the mi...
by ramdom
Wed Sep 09, 2020 2:44 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

If you are talking about the banding when you say "this is not normal", since you have PI, just run CBR default on it - the banding entirely disappears. I had some banding issues but found I could correct them by applying CBR on the master light (I also did CBR after calibration and then integrated ...
by ramdom
Wed Sep 09, 2020 2:41 am
Forum: Image Processing Troubleshooting
Topic: New to Startools - can you do better with this 53 hour O3 master light?
Replies: 20
Views: 1469

Re: New to Startools - can you do better with this 53 hour O3 master light?

For of all, thank you for taking the time to do this. I am unclear as to what you're saying when you wrote this "This is not normal, nor is it celestial signal " Are you referring to the fact that there's still a gradient? The middle is dark and the outside isn't? (All that goes away once I do a Can...