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> > Small screen shots of a
> > 640x480 screen will be vastly more legible than from
> > a 1280x1024 screen.
>
> What?!? Screen size has nothing to do with clarity or
> scaling. A fixed-size dialog is captured and saved at
> the same size and quality regardless of screen size.
> Try it. Take a 300x300 pixel dialog, capture it at
> 640x480 (which is an unusable screen size unless
> you're running Win 3.1 or possibly Win 95), 800x600,
> and why the heck not jump all the way up to 1600x1200
> (which is what I work in). All screen shots will be
> the same file size, quality, and physical size.
For an individual dialog box, sure, it's irrelevant.
But I was talking about full-screen shots, which suffer the biggest
legibility problems. The invariant size of objects when measured in pixels
means that they take a larger fraction of the screen when you reduce the
screen resolution -- in effect, magnifying the objects.
If you scale your screen shots to, say, five inches wide on the printed
page, a 640x480 screen image works out to 96 dpi, an 800x600 screen to 160
dpi, and a 1600x1200 screen to 320 dpi. This is a very simple way of
increasing the readability of full-screen shots. It works with lots of
applications, though some use enormous dialog boxes that will defeat this
approach.
> > It's easy to blur pictures by accident by scaling
> > them unnecessarily.
>
> It is rarely necessary to scale screen shots unless
> you're doing so for some kind of artistic purpose
> outside of making them fit on a page.
My point exactly. There's a lot of unnecessary scaling going on out there,
and it can lead to blurry pictures.
> > Having
> > the wrong settings in Distiller will do it, for
> > instance.
>
> That's not scaling. In fact, well, that's a topic for
> another lengthy discussion.
Downsampling is scaling. When downsampling, Distiller reduces the dimensions
of the bitmap (as measured in pixels). That's scaling. Later, the PDF
reader will take this reduced bitmap and stretch it to match the specified
bounding box (as measured in inches), which has not changed from the
original. That's scaling, too. (I wouldn't call color-space reduction
"scaling," but color-space reduction shouldn't be an issue with screen
shots.)
