I just installed a new widescreen flat-panel monitor for my computer; I'm
currently in the process of adjusting its colors, tint, gamma, etc. (This never
seems to be easy; it used to be a LOT easier on my older CRT monitors.)

But I've noticed-- after all these years!--a strange phenomenon when using
POV-Ray's 'gamma adjustment' instructions at  "3.2.3.2 Setting your Display
Gamma" -- specifically concering the image there, that goes from gamma 0.0 to
gamma 3.0 in steps.

That image has been part of POV-Ray for a long time-- probably created when the
world still used CRT monitors(?) But I'm wondering if a new 'kind' of image may
be required, for setting up modern monitors.  In a nutshell, it seems that the
'proper' visual gamma of the chart *changes*, depending on the visual SIZE of
the chart on the (discreet-pixel) monitor, vis a vis the monitor's chosen
resolution (and/or the number of discrete pixels it has)--  specifically, the
appearance of the black/white horizontal 'comparison' lines next to the gray
swatches.  I could be wrong, but their appeance seems to depend on whether the
lines actually 'line up' with the monitor's pixels...the result being an
apparent change in what should be the 'proper' gamma.

As an experiment, I downloaded the gamma chart image and brought it up in
several of my image apps. There, it's an easy matter to reduce the screen size
of the chart... not by actively reducing its pixel count, but by simply using
the app's 'magnifier' tool. A *smaller* appearance of the chart changes what WAS
a proper 2.2 gamma appearance to a gamma of 1.0! Of course, the app itself (or
the monitor or computer?) must be using some kind of internal 'blending' to do
this, which may be the reason--so I could be wrong about my method. But it's
something I noticed-- in a less extreme way-- when using just the POV-Ray help
file and  its chart, when I changed the monitor's resolution.

All in all, this is technical mystery to me. Comments are welcome; I'd LIKE to
be proven wrong ;-)

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