PetteriAimonen / focus-stack

Fast and easy focus stacking
MIT License
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Dead pixel handling #47

Open anjok opened 5 months ago

anjok commented 5 months ago

In astrophotography, there are calibration frames of various types, in particular darks, where you cover the lens and takes some shots. The resulting image(s) will show only dead/hot pixels. From those images, you create a master dark by simple averaging.

In the actual stacking step, you then subtract the master dark from the images so you can prevent artifacts like the ones below.

Another way to handle this is to check if the image has pixels which are "unnaturally" different to the previous aligned images, but that's probably easier than in astro, where you have mostly the same image, unlike with focus-stacking.

Can we have an option to add a dark image to subtract or should we use something like imagemagik instead?

image
PetteriAimonen commented 5 months ago

Sounds like a reasonable feature but I have no plans to implement it myself.