[mariner10 (Steve)]

Hey Rick,
As soon as I read your response it made sense so again my thanks. I'm about to give it another go.

Steve.

Originally Posted by RickS

Hi Steve,

Thanks for sending me some data to look at.

I started by looking at the calibration masters. I made a small representative preview in the master bias and copied it to the master dark and the master flat. Using the Statistics process I found that median values (as 16-bit integers) for my preview area were approx 4163 for the master bias, 12 for the master dark and 13724 for the master flat.

Now, this tells me that you have definitely created the master dark with bias calibration enabled (otherwise the median value of the master dark preview should have been greater than the 4163 of the master bias.)

Your error message was:



So, you've calibrated the lights and told ImageCalibration to bias calibrate the master dark (Applying bias correction: master dark frame ...) which you already did when you created the master dark. So, as I guessed, you've subtracted the master bias from the master dark twice and that's the cause of the error.

I ran ImageCalibration without attempting to bias calibrate the master dark again (see first attached image) and it worked without error. I then debayered one of your 600s subs and it looks pretty good (see second attached image.)

I also checked the master flat and found some dust donuts. The calibration appeared to remove these nicely so all is well...

Let me know if any of this isn't clear.

Cheers,
Rick.