Thanks for the tip Bert.
But i've used this Registar function a few times in hope that in contained "miraculous powers" in matching mosaic frames. But it fell short, with all hope rapidly turning to despondency.
What I didn't understand as a part of this Registar process was whether it took a sample of pixels from each image to match or the entire image. It is noted in the manual: "In order for a source image to be successfully calibrated, it must have at least 1000 pixels in common with the reference image. If this is not the case, no calibration is performed and a warning message appears." So does this mean it only takes a sample of 1000 pixels. Is only the background averaged and sampled - what happens if one frame has a bright globular cluster, will this be included in the calculation?
I guess the manual does warn you:
"Note: The Calibrate command is most useful if the source image(s) are similar to the reference image. If the source and reference images are inherently different, or have stars of substantially different sizes, this command can return unexpected results."
I do any brightness matching in photoshop with initial work either using DDP or pixel math - the old "clunky" way, but it works and is extremely flexible. Perhaps you've had more experience with the function and can shed some light on any preprocessing you performed to make it work as documented. If it can simplify the process I'd be happy, but perhaps there are no free lunches!
