Please check/adjust your monitor settings. Photographs prepared for such
presentations usually suffer from a lack of detail in the highlight and
shadow areas, and can appear too bright or too dark, depending on your
monitor settings.
Monitor Calibration
If
you would like to check/adjust your monitor, look at the greyscale
below. You should be able to see all 24 distinct shades. The leftmost
bar is pure white - nothing should be brighter. The rightmost bar is
pure black - nothing should be darker. Pay particular attention to the
first 2 and last 2 bars.

To
make adjustments, if needed, use the buttons on your monitor.:
-
Turn the contrast all the way up (100%)
-
Turn the brightness all the way up (100%)
Now,
while watching the greyscale, turn the brightness back down to the point
where you can just distinguish between the two rightmost and two
leftmost bars.
In
many cases, 100% works best for contrast and between 95% and 100% for
brightness .