Poor Image Integration

[Andres.Pozo]

I then calibrated my lights with only the Master Flat subtracted, without Dark or Bias subtraction.

I think that you can't apply the MasterFlat without having applied before at least a Bias. Also the MasterFlat itself must be Bias/Dark calibrated. The calibration is a sequence where its steps are not independent and the can not be applied isolated.

[georg.viehoever]

I then calibrated my lights with only the Master Flat subtracted, without Dark or Bias subtraction.

I think that you can't apply the MasterFlat without having applied before at least a Bias. Also the MasterFlat itself must be Bias/Dark calibrated. The calibration is a sequence where its steps are not independent and the can not be applied isolated.

Thats correct. Basically, you should be doing (lights-bias)/(flats-bias), and this is different from lights/flats. Simple math.... And if there is dark current, this should be considered as well.

Georg

[Philip de Louraille]

I used auto background extractor on the first jpg (!) and removed quite a lot of the gradient. I would think it would do a much better job from the 12- or 16-bit image still in linear mode.

[Doug]

Thanks for all your comments.
I'll try out more tests and see where I get to.