Lightness / Darkness of Images

This was inspired by "Just Visiting" below, with the dark JPGs. Since I view
my images (Canon Ixus 700) on my PC screen, which has a variable brightness
control, how do I know whether the images are at the correct brightness?
I might view it as OK, get it printed professionally and find that it is too
dark / light! It the printing process involves an automatic light correcting
step, how would I protect something which should be a bit darker / lighter
than standard?

Dave W.

There is no reliable way to control brightness, contrast, hue, saturation
etc unless you "roll your own": manipulate and print your images in a color
managed workflow (calibrated monitor, color managed photoprogram, good
quality printer). Perhaps you can get your P&S jpeg images printed by a
custom finisher. Otherwise you're SOL unless you want to invest the time and
money to get the results you want.
Printer manufacturers have tried all kinds of tricks to substitute for color
management but they do not work reliably, in part because many users'
monitors are wildly too bright, too warm toned, etc.
Additionally if you learn to use a program like Elements you can seamlessly
adust the color/contrast/hue etc of particular parts of an image, get rid of
flash highlights on noses and chins, etc. This type of image manipulation
will greatly improve your finished pictures and once learned takes very
little time per snapshot type image to perform.
Short of absolute control, if you run your images through a photoprogram
that has a decent all in one optimizing filter you may get better printed
results from mass market printers. These optimization filters generally work
by identifying the blackest and whitest parts of the image and trying to
normalize the historgram within that range, along with formulaic tweaks to
contrast and saturation. In fact this is what the mass market finishers
should automatically do prior to printing anyway, although you may not like
the settings their programs choose for your images.

Dave W wrote:
This was inspired by "Just Visiting" below, with the dark JPGs.
Since
I view my images (Canon Ixus 700) on my PC screen, which has a
variable brightness control, how do I know whether the images are at
the correct brightness? I might view it as OK, get it printed
professionally and find that it
is too dark / light! It the printing process involves an automatic
light correcting step, how would I protect something which should be
a bit darker / lighter than standard?


A reasonable beginning would be to adjust the brightness of your
computer monitor so you can discriminate between neighbors on a gray
scale, especially between members of the end pairs:
http://www.fototime.com/C19110B537B18A8/orig.jpg
http://www.fototime.com/6811220294ABBE5/orig.gif

That should give you an idea whether your viewing is way out of line
or not.

Plenty of on line resources to get it close, or even perfect.

--
Frank ess