re: filmscanners: Vuescan blue anomaly

[rafeb <rafeb@channel1.com>]

At 12:41 PM 7/25/01 +0000, Lynne wrote:
>Rafe wrote:
>
>>"Auto Levels" is a bit of a sledgehammer approach to
>>color correction.  Not very subtle, and quite often
>>wrong.
>
>Yes, but it's quick. When you're working on images that differ greatly in 
>subject, film, time of day, and exposure (and I always am), it saves a lot 
>of time to get color casts, levels, etc. out of the way right away so you 
>can do the *real* corrections. :-)


I disagree with the last part of that paragraph.  
By the time "Auto Levels" is done with your image, 
it may have mangled it beyond repair.

Go ahead and use it if you're in a hurry -- most 
of the time, it does more or less the right thing. 

A far better approach, IMHO, is to set the black 
point/white point with the droppers in either the 
Curves or Levels tool.  There, you have much more 
control -- 

* You can set black point to any RGB value you like
* Ditto for white point
* You can *place* the black point where it's most 
  appropriate within the image.
* Ditto for white point.

The latter approach only takes a bit longer than 
"Auto Levels" but allows much greater control, with 
little chance of losing critical image data.

"Auto Levels," IMHO, gives far too much freedom 
to the machine -- the freedom to screw up my photo. 
No thanks... <g>


rafe b.