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RE: filmscanners: Hello



Ken writes ...

> ...
> ...   I've tried out Photoshop Elements and
> like it, but at this point am wavering as to whether I should get the
> whole PS6 package or if PSE would do it. Any advice appreciated.
> ...

  From what I've heard, PSE should be able to take care of most anything
you'll need ... but on lists like this one, you commonly here the phrase
"I'm not famaliar with PSE ...".  You can however register for a very good
forum at www.adobeforums.com.  Note too the "color management" forum on the
right side of the wwwpage.

> ...
>
> So I have a lot to learn about color control, and have basically zero
> experience with color management.  But I'm not doing a lot of printing
> just yet, so that's probably not my first concern.  To start with I'd
> appreciate a good explanation of "gamma."

  When talking about "gamma" you cannot avoid putting it into the context of
"blackpoint" and "whitepoint".  As you imagine, every device has its own
"black" and "white" ... "how black is the black ink, and what color and how
bright is the paper?" ... "how black is your monitor, and how bright is
it??" ... "how dense is the deepest shadow in your slide, and how bright are
the specular highlights???"  Every device has a inherently different black
and white, but they need to be transferred from one device to another.
"Black" is pretty much straightforward, but "white" may have a color
associated with it (a color temperature ... 5000K, 6500K, ...), besides
having an absolute brightness or reflectance.

  Well enough ... what is "gamma"?  Gamma is also device dependent, and it
is the device's response to the stimulus (data).  If the device is
stimulated with a tone and the same tone is presented, its gamma is said to
be 'one'.  However, this is always never the case ... even for our own
eyesight the perceived tones between dark and bright are different than the
stimulus.  Any deviation of from the stimulus (or data) and what is
perceived is best fit to a power curve, and the exponent of this power curve
is "gamma".  Most devices, and even our own perception, have a gamma
approximately 2.

  I have left a lot out, and I may have said more than you need to know ...
but "gamma" is very important to your first attempts at understanding the
relationships between devices and managing their color.  Also pay attention
to color or device "gamut".

  My favorite text on this subject is "Real World Photoshop 6", and you can
get a flavor for the book and a brief understanding of the concepts here:
http://www.creativepro.com/author/home/40.html

  good luck and welcome to scanning films ...

shAf  :o)




 




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