I know how to turn on Quick Mask and paint a selection -- turn it into
an alpha mask and save the image with the alpha mask and it works fine.
Where I get totally lost is when I want to re-edit (re-open the image) the image
later and change the alpha mask/channel.
I've googled for information but all of what I find is years old and
don't quite apply to the current release. Other stuff on some forums is
so vague and convoluted that I get lost trying to understand what they
are trying to do.
What I want to do is simple -- I just want to change the shape of the alpha
mask/channel to make it cover or reveal other parts of the image.
Where would a SIMPLE tutorial be on just doing that?
For example: I have a transparent spot in the middle of the alpha mask/channel
that I want to make opaque so that I can see the image in that spot again.
How do I do that?
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