Ok, since baby decided not to sleep last night, we made some time in the observatory. Need to get them loving the stars early . I took some light frames, some dark frames, and flat frames as well as some flat-darks. I have included the master dark, the master flat, and the master dark-flat in the dropbox link along with the integration of the lights with no flats and with flats. I have only included a few uncalibrated lights since I have used up my dropbox space, heh heh. Here is the executive summary:
The flats are overcorrecting. I was only able to get data for OIII, but that's where most of the problems seem to be located, so I started there. The stack of lights calibrated only with the dark frames show a definite darkening on the right side of the frame. The flats look to show that as well. But, when I calibrate with both darks and flats, the areas that are dark in the flats are significantly too bright in the calibrated lights, thus showing overcorrection. I included the dark-flats in case you can see any sign of a light leak. The stack look pretty clean to me. I made the dark-flats in the daytime with the observatory closed and only a lens cap over the telescope. I figured if there was a light leak that it would make itself known pretty quickly as the ADU values with go up significantly as it was daytime. This did not happen.
As a note, I took the flats with a light panel placed over a what t-shirt that was used as a diffuser. The shirt was flat across the lens opening. I also tried raw sky flats, but I have some high clouds right now, so I can only confirm that raw sky flats show the same darkening on the right side, but they are not high quality enough to actually use in calibration since the clouds cause some problems.
Here is the stack of lights calibrated with darks. The stack was 30 OIII lights taken at 120s. I integrated without registering them so as to keep the edges as clean as possible. They have been stretched to show the problems. You can see a region to the right and left that are darker than the rest.
Here is the stack of lights calibrated with both darks and flats. The flats have been calibrated with flat-darks as well, although they were only .75 seconds each, so there was not much dark current to take care of. The regions that were dark are now far too light.
I have included a link to my dropbox which contains the masters and a few raw light frames. I uploaded until I ran out of space. Here is the link to the dropbox: https://www.dropbox....kzaddRyXUa?dl=0
What are your thoughts on this? Does this look like a light leak on the flats? There is clearly some issue with the green-blue region of the spectrum when it comes to these particular areas of this cmos chip, however, I have trouble understanding why they show up in both the flats and the lights, but the flats just overcorrect for them. If anyone has any ideas, I am open to trying them.
Thank you so much for all of the time you are spending looking at my problems.