On Fri, 2009-06-05 at 12:24 +0100, laptop wrote:
> > I was following this tutorial.
> > http://digital-photography-school.com/precise-color-cast-correction-with-gray-fill-layers
> > I added a 50% Gray Layer (7f7f7f), Mode: Difference. I picked a point
> > that was black, referencing the Pointer Dialog, and jotted down the
> > x/y coordinate found in the lower left-hand corner or Pointer Dialog.
> > I brought up the Levels Dialog and clicked the middle eye dropper for
> > picking the gray point, and carefully relocated that same x/y
> > coordinate.
> > My question, is there another way to remember or set the gray point,
> > or remember any point for future reference/recall?
> Have a look at Sample points dialogue.
One thing you might try is having selected and marked your mid grey
point, use the Levels tool to remove any cast by making the red, green
and blue channels equal. You can follow the changes in the dialogue of
the sample point you have marked.
I tested this by introducing a colour cast and then going through the
process. The only real difficulty I encountered was in finding a true
black point. But then, I don't think it matters.
If you should try this process I would love to learn how you get on.
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