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RE: [APML] PixInsight questions ( was:Two New Images)
>So let me get this straight, as long as you linearize the film by adjusting the >gamma before dividing, as suggested in your tutorial, you should generally >use division rather than subtraction since it performs better in "preserving" >the data (i.e. the objects you are trying to uncover). Right?
Hi Wade
I would say that division corrects the data better. That means, objects in the outer regions become brighter, and those in the center dimmer. If you have very faint nebolosities in the outer regions you will be able to "extract" them from the background more easily, without oversaturating the brighter ones (ussually in the center).
Another good point in a division is that the color of the objects is more accurate in the whole image. You can check that with a big mosaic... Wei-Hao's MW had some purple casts in the corners of each frame, that were corrected with a nonlinear division.
Regards,
Carlos Milovic F.
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