One of the confusing aspects of PMV's support is the multiple channels it can take. The Betas list. Private email. Public forum.
To aid others who may run into a similar situation as mine, I am posting the "answer", as received via email from Peter. Posting publicly allows others to search, and maybe even find, information about this in future.
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Re: Cut area color variation (before and after Paste)Thanks for the image. I can repeat the scenario here. I am glad to tell
you that it is not a bug.
The image is 256 colors, and hence opens in color mapped mode (8 bit color
map). The background color for color mapped images is 0, and is white in
this image. Doing cuts will fill the area with index 0 (white). For color
mapped images, the background color has to be one of the indexed colors.
This means that if the image only has shades of red and blue, the color
used for filling a cut will be a shade of red or blue - the color at
index 0. It cannot be anything else, since PMView is limited to using one of
the colors in the color map. To keep things consistent, PMView always uses
index 0. (PMView *could* of course try to search for the color closest to
black, but this could lead to very inconsistent and confusing results).
When pasting into a color mapped image, the resulting image will
always be deep color. In deep color mode all colors are available, and PMView
always fills with black.
So, in your case you first cut in 256 color mode and the area cut out
gets the background of index 0 (which happens to be white for this image. Like
I said, it can be any color, depending on what is on index 0). When you
paste, the image is converted into deep color and now if you cut out an
area, it will be filled with black.
Working with color mapped images can be very confusing. I would recommend
that you always convert to deep color before starting to edit.
Alternatively, you could convert back to 256 color immediately after
doing any operation that switches to deep color. (For instance any
interpolation, e.g. resize or rotate, will also convert to deep color).
Hope this helps to explain what's happening.
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Hello, Peter:
Thanks for taking the time for your detailed explanation, which I understand.
> Alternatively, you could convert back to 256 color immediately after
> doing any operation that switches to deep color.
This is probably what I will do, now that I know that a Paste operation triggers a switch to Deep Color. I see another keyboard shortcut definition in my future

> (For instance any interpolation, e.g. resize or rotate, will also convert to deep
> color).
Hmmm. I do a LOT of resizing, cropping, and rotating. So much so that I have keyboard shortcuts set up for resize and rotate at 90°, 180°, 270°.
Just checked, and rotating and resizing doesn't _appear_ to trigger a mode change to Deep Color: the image's status bar says the image is still 254 Grays" after a resize or rotate, even if the rotate is at an Arbitrary Angle.
But Paste definitely does.