Yo Jim,
This needs a bit more testing, I think. I'm getting different results.
I think what might be going on is along these lines:
When you apply compression to a given image, it may or may not be changed.
If it's a rather large image but you've made it small in the PPT file, the change is immediate
and obvious when you apply compression, especially if you then enlarge the image.
But if you choose a high DPI compression level on an image that's not too big (in pixels) but is
large on screen, it won't be compressed. For example, if you set 220 dpi compresssion on a
1024x768 screen capture, it probably won't do anything to the image if it's over 4.65 inches wide
(1024 / 220).
The compression takes place immediately. Or not (as above). I figure the compression setting
does affect the Save As Picture quality, but indirectly; it's already changed the image in PPT,
so of course the exported image is different.
Also, I don't find that it's reversible ... that is, take that same 1024x768 screenshot, reduce
it to an inch wide or so, set compression to 96dpi. Now enlarge it to fill the slide. Fuzzy, as
you might expect. Now try to get the lost resolution back. Other than via Undo, no can do. ;-)
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Steve Rindsberg, PPT MVP
PPT FAQ:
www.pptfaq.com
PPTools:
www.pptools.com
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