I think there’s something wrong when creating a MasterDark with Image Integration and Dark Calibrated subs on an Apple computer compared to using a Windows computer. I’ve attached a screen shoot showing the difference between a Debayered AppleMasterDark created on the Apple and a Debayered WinMasterDark created on a Windows 7 Dell, showing how these two MasterDarks calibrate a single Dark sub # 0612. This screen shoot show on the left side of the screen the two Debayered MasterDarks and on the right a single Dark sub, note the difference in pixel levels.
I followed these instruction,
http://www.astrofoto.es/Adler/Documentation/Calibration/Calibration.xpsm2I used my Canon T1i CR2 files, the Bias subs (41 total) are at 1/4000 and iso100, the (14) Dark subs are 120sec and iso400. The first Windows test started with the CR2 files, creating/Image integration a WinMasterBias from 41 .fit converted CR2 files and then Calibrating the 14 Dark CR2 subs, to create with Image Integration a WinMasterDark. I then proceeded to Calibrate a Light and a Dark sub. This Windows test worked properly, I then used an Apple MasterBias for Calibration on the Windows computer with success, I then used the 14 Apple Dark Calibrated sub on the Windows computer to create a second Windows MasterDark , this new Windows/Apple MasterDark worked properly for Calibrating on the Windows computer. When I tried to use the Apple MasterDark on the Windows computer the Calibration of the Light and Dark subs was defective, if I used the WinMasterDark on my Apple computer for Calibrating these same two subs the Calibration worked properly .
Check this link.
http://pixinsight.com/forum/index.php?topic=3671.0 Cleon
PS I corrected my Screen shoot of the AppleMasterDark