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California Nebula calibration frames problems

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#1 wheelers4life

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Posted 15 February 2020 - 02:14 AM

I think I'm having calibration frame problems. I will explain what I do and see if I'm doing something wrong. This is an image of light frames 15x300s, Darks 20X300s, Dark Flats 40X.07996 Flats 40X.07996. Integrated in pi and hdr toning in ps. Then resized in windows photo viewer for this forum.

Ok So I used N.I.N.A. for light frames I think this is why id did not frame right I have been having so,e problems with plate solving in nina. After the lights were taken. I took a white tee shirt and placed it over my dew shield and used a rubber band to keep it there and pulled all wrinkles out. Then set up my light panel right on the dew shield and used apt and opened up ccd flats wizard and let it do its thing, when it uploaded to the camera I shot my flats, Then I pulled my camera off the hyper star and placed the camera lens on and put it in a box. I shot my dark flats the same exposure as my flats both took 40 frames. Then shot my dark frames with the camera still in the box. It looks like I have some color differation on the top right and bottom left corner of my frames. I used pi to integrate my darks and dark flats using the pi book. Then used these frames to calibrate my flat frames. Then integrated my flat frames with pi. Next I calibrated my lights with the dark flats, Darks and flat frames. Did a debrayer, and star aligned then lastly I integrated my aligned frames.

Thanks

Danny

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  • California_Nebula2.jpg

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#2 richorn

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Posted 15 February 2020 - 01:09 PM

OK, I will start with a couple questions.

 

First, you don't mention temperature.  From your signature it appears you are using a cooled camera.  What temp did you use for all of the above? Did you match temps for all files?

 

Second, you started in NINA.  Is there a reason you didn't use NINA for the calibration frames as well?  I have read here and there that different softwares treat images differently.  So it is possible you are getting some differences in the APT images compared to the NINA images.  Also, I do not understand why you remove the camera to do darks and dark flats...

 

Nina has a very capable flats wizard with matching dark flats. You can also add darks to the image sequence.

 

A modified workflow could be:  Set up the system at twilight, and run the flats wizard in NINA.  Pull the light panel, and cap/cover (for full dark) for dark flats and darks.  Then do your polar align and run your sequence for the nights light image capture.  You will probably lose bit of image time after full astro twilight, but your calibration frames should be more reliable.

 

My $.02.

 

As to your existing problem, I can only assume the different capture methods created a problem, but the details are way over my pay grade!  ;-)



#3 wheelers4life

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Posted 15 February 2020 - 10:51 PM

My camera cooler is set at -20. Yes same temp for all calibration frames. I can never get nina to work on my flats. It keeps saying light is to bright. I have put three shirts over and dimmed my panel down to the lowest setting. I use a dew shield and when I cap the dew shield for darks there is a red glow from my camera light. That's why I started removing the camera and capping for darks and dark flats. I bought some black electrical tap today. Tomorrow should be good for a little bit of imaging. I'm going to put a strip over the red light to see if that will help. I appreciate all the help. I will never get better without criticism. So I'm ok with that. I took 30 subs but I do not have a dew heater yet, and after about 12 frames my corrector froze over as it was 27 degrees outside. It was the first time out with my new guide scooe and I wanted to try it out. At least I was able to get it working good. Tomorrow I'm going to try the framing assistant in nina and try to frame better

#4 sunnyday

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Posted 15 February 2020 - 10:58 PM

I can't help but I find her pretty anyway.



#5 wheelers4life

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Posted 16 February 2020 - 12:05 AM

Thank you. I'm not trying to be professional  but want to get better. And it seems all the videos on calibration files show about the same thing. Not much on teaching. I'm doing what they are showing. Taking flats with a white tee shirts stretched across my dew shield and histogram in the middle with a adu setting of 25000 is what I was told my my camera. But for some reason I still see vignetting.



#6 richorn

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Posted 16 February 2020 - 12:53 AM

I am going to suggest that you stick with NINA. I think the solution is to reduce the light source until NINA (flat wizard) doesn't complain about the brightness. I would also use NINA to get matching darkflats and darks.

 

At least give that a try and see if you can properly calibrate the images taken that same night.  

 

One step at a time!

 

BTW, I had similar issues with flats for a few months. I gave up and threw money at it lol!  The Flip-Flat is freaking awesome!



#7 wheelers4life

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Posted 16 February 2020 - 03:12 AM

This is the same image I reloaded into pi and tried out dynamic back ground extraction. and then used starizona star-tools color smoothing and star killer. I think this one looks way better. 

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  • California_Nebula_DBE.jpg



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