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can't remove noise

Posted: Tue Jan 26, 2016 10:38 am
by alacant
Hi

My first go at st so please be patient:)

I'm having great difficulty getting noise removed from my dss fits file. I've followed many YouTube tutorials and I'm beginning to wonder whether the stack is at fault:
<edit>
https://drive.google.com/file/d/0B_uUt0 ... sp=sharing
</edit>
autodev really messes up the image and I can't retrieve it. Using dev is a little better but although I can see some detail, the noise reduction is poor.

Maybe it is the iso speed in camera:
nikon d40 at iso 800 then 12 or so light frames at 10-20 seconds with dark, bias and flat frames which *seem* to have worked but...

Any help especially if someone could check the fits file and comments on iso in camera before I spend any more time would be most gratefully recieved.
TIA

Re: can't remove noise

Posted: Tue Jan 26, 2016 1:17 pm
by Burly
Try auto dev-keep-crop-keep-wipe-keep- now dev manually stretch too suit -keep -work through modules turn off tracking at end of processing then denoise , hope this helps .

Re: can't remove noise

Posted: Tue Jan 26, 2016 3:38 pm
by alacant
Hi
Thanks for that sequence. It's a lot better. I used the hds reveal, but that's the only module I used, I'm having problems with the colour cast. It seems to be red and also the stars have bloated. Do we have modules for colour and 'fat stars'? In the nef files the stars are quite sharp points.
Do forgive the newbie questions and thanks again, I feel I'm getting somewhere.
m42all.jpg
m42all.jpg (200.2 KiB) Viewed 11092 times

Re: can't remove noise

Posted: Tue Jan 26, 2016 6:01 pm
by Burly
Dropbox your fits file so peeps can take a look at data .

Re: can't remove noise

Posted: Wed Jan 27, 2016 10:19 am
by alacant
Hi
There's a public link to the fits in the first post. Is that OK instead?
Thanks for your interest.

(I can Dropbox it too later if necessary)

Re: can't remove noise

Posted: Wed Jan 27, 2016 1:26 pm
by Burly
You may want to amend that link :D think you picked the wrong file comes up with some sort of exam pdf

Re: can't remove noise

Posted: Thu Jan 28, 2016 7:05 am
by alacant

Re: can't remove noise

Posted: Thu Jan 28, 2016 9:44 am
by Burly
Thats m45 though i think your settings in DSS need tweaking ,did you set matrix pattern for your camera in fits settings ,im no expert but your stars are bloated may be the cause

Re: can't remove noise

Posted: Thu Jan 28, 2016 12:49 pm
by alacant
Hi
Sorry. I posted the wrong fits. This is M42:
https://drive.google.com/file/d/0B_uUt0 ... sp=sharing

I didn't have my camera, a nikon d40 listed in dss so I put nikon d50 which I think has the same sensor. Also, it was full moon and I used iso 800. Would this make a big difference?

Thanks for having a look.

Re: can't remove noise

Posted: Thu Jan 28, 2016 3:18 pm
by Burly
im not sure maybe ivo will have a better idea to whats causing bloating of stars .