In the ImageCalubration process, there are sub-sections for Master Bias, Master Dark and Master Flat. In each of these sub-sections there is a check-box labelled "Calibration".
Believe it or not, it was only yesterday that I finally understood 'how' these check-boxes work - and it was
not as I had thought
They would make a great deal more sense if they were labelled as follows:
For the Master Bias sub-section, label the check-box as "Calibrate Biases using Overscan"
For the Master Dark sub-section, label the check-box as "Calibrate Darks using Master Bias"
For the Master Flat sub-section, label the check-box as "Calibrate Flats using Master Dark"Further, each check-box should be 'greyed-out' by default, and should only be 'enabled' if the preceding sub-section can provide the required information to allow the calibration step to take place.
As things stand at the moment, I have been looking at the check-box and interpreting it as "if
this check-box is ticked, then
this master image data will be used to 'Calibrate' the
next sub-section".