In message , Peter Jason
writes:
Hi, I wear glasses for astigmatism etc and I wonder if it's possible
to buy a monitor whose screen can be adjusted for this & similar
conditions?

What a fascinating question, and excellent lateral thinking on your
part!

I thought I knew what astigmatism was, and just checked with wikipedia,
and it's a lot more complicated than I thought - so I'll go with my
original thought, that it means the lenses in your eyes mean you see the
world as either stretched or compressed vertically - circles appear as
ovals, and people appear either tall and thin or short and fat - and
your glasses correct for this. And you were wondering if it's possible
to find a monitor you can use without wearing your glasses.

Depending on your degree of astigmatism, an old CRT monitor with height
and/or width controls might be of use, but not only will those now be
hard to find, but I don't think the adjustment is very much.

An alternative would be to deliberately set your graphics card
(including the in-built one if it's a laptop) to a resolution that's the
wrong aspect ratio for your monitor. I've seen people do this often
enough in practice, by mistake (most commonly feeding a widescreen
monitor with a 4:3 signal); it had never occurred to me that it might
actually be useful!

If your astigmatism means you see the world stretched vertically, then
using a widescreen monitor (the common type nowadays), but with the
graphics card set to suit a 4:3 monitor, will give you fat pictures. If
you naturally see the world as short and fat, then using a widescreen
mode on a 4:3 monitor (you can still get them, I think - just harder to
find. Should be able to find them second-hand no problem!) should help.

Three problems with this "solution":

0. With any monitor that has a "native resolution", i. e. pixels, which
means any modern flat-screen monitor, using it at other than its native
resolution (or an integral fraction thereof) will result in _some_
blurring. This may still be acceptable as the cost for not wearing your
glasses. (It won't apply to a CRT monitor!)

1. Some modern monitors and graphics cards talk to each other, which
might mean that the graphics card knows what shape the monitor is, and
may refuse to offer "incorrect" resolutions. To get round this, you
might have to do one or more of the following: select "generic" rather
than specific monitor; use analogue (SVGA) rather than anything more
recent (IMO, the difference is far less than claimed in most cases - not
visible to me); even with SVGA, you might have to cut a wire/pin.

2. The range of ratio "corrections" (distortions) available will be
limited - possibly only to the difference between 16:9 and 4:3. You can
expand the range somewhat by turning your monitor sideways: modern OSs
(I think XP on, possibly earlier) have the ability to turn the picture
sideways, though how to invoke it isn't widely known. (Sometimes it's as
simple as the arrow keys with other keys.)

There are utilities that can force your graphics card to output
non-standard resolutions; I imagine how well these work varies from card
to card. (Note that in extreme cases this _could_ damage the monitor,
though I think only for very old CRT ones - modern ones, including later
CRT ones, usually detect "out-of-range" feeds, and pop up a notice to
that effect on screen, or at least just go blank, or display an unlocked
picture.)

I'd say it's definitely worth investigating these avenues - conventional
monitors (of the two shapes) used with unorthodox resolution settings,
and the possibility of using them sideways.

P. S.: before messing with resolutions (including going sideways), I'd
say it's worth getting hold of one of the free utilities that can store
your icon positions, and put them back: changing resolution does tend to
muck them up. I normally use iconoid (https://www.sillysot.com/ - yes,
that really is the URL!); another, slightly quirkier one but the only
one I know that actually has the option to save the settings in a real
file rather than buried in the registry somewhere, is desktopOK.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

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