Draco Galaxy Group

Comment

Comment by Russ Ruggles on December 13, 2013 at 5:17am

Typically, I use the histogram as my guide to how long to expose for flats. I start at the fastest shutter speed and work down from there. I try to keep the histogram peak in the middle - a tad to the left is OK too. I also shoot 21 of them. I read somewhere that odd numbers for calibration frames work better. It's all subjective if you ask me so do what works for you. BYE is great for shooting flats. Once you find that happy shutter speed, set your quantity and let her rip. Takes about a half a minute.

Comment by Russ Ruggles on December 13, 2013 at 5:06am

Flats on file? John, flats are one of those calibration frames that cannot be used over and over. Darks - yes. Bias - yes. It's important to take flats through the imaging train with nothing changed between the lights and the flats.

Comment by John Auvil on December 12, 2013 at 4:09pm

Thanks for the tips guys. I have some flats on file that I'll incorporate into the image stack and see how it turns out. BTW do you recommend a typical exposure length for flats?

Comment by Russ Ruggles on December 11, 2013 at 2:34pm

Yes, flats would help with the illumination across this image. See how it's light on the left and dark on the right? It would help to balance that. Also, if you enable dither in BYE with PHD to every 4th or 5th image you'll get rid of most of those background streaks. The dither time add only a few minutes to a session.
I'm tring to figure out your "stats" on this one. It looks like you have 1 minute and 14 seconds of total imaging time. That can't be right.

Comment by John Auvil on December 11, 2013 at 2:18pm

Bob, I have in the past and didn't see any benefit. Would flats help with the cloudiness in this image? I figured that it was from the cirrus clouds that rolled in during this imaging session.

Comment by John Auvil on December 11, 2013 at 2:16pm