Originally posted by K5-0 Love it! When you say dark and bias frames, you mean you shot with exposure bracketing right?
Can I assume you used astrotracer to get a 10second exposure on a 135mm lens?
Thanks ! Yes I did use astrotracer I forgot to mention it....
The calibration frames are as follows:
Dark frames: same exposure and ISO as your comet shots, lens cap on (to remove thermal signal from the sensor)
Flat field frames: shot an evenly illuminated target (I use an electroluminescent panel) at base ISO, with correct exposure (to correct accurately vignetting)
Bias frames: shortest exposure at base ISO, lens cap on (to correct the zero value of each pixel). They are needed for an efficient use of flat field frames.