RE: [APML] A Curves Exercise [was: Histograms, curving and layers]

[Matt BenDaniel <matt@starmatt.com>]

At 14:19 05-12-02 -0800, Alan Voetsch wrote:
>Matt,
>
>--- Matt BenDaniel <matt@starmatt.com> wrote:
>> To load a curves file, open a curves dialog in PS
>> (Image->Adjust Curves  or  Layer->New Adjustment
>> Layer->Curves) and click on the Load button.
>
>What will the load button do? Is it for incoming
>images, or outgoing?
>
>> I then adjusted
>> the black point to 15, 15,
>> 22 and looked at the result.
>
>Black point, white point. What are they? Will I need
>to learn how to use them? Careful here, I'm trying not
>to over-reach. I want to be able to master what I
>learn, if too much is thrown too quick, I probably
>won't be able to assimilate it.

Alan,

These tools are pretty basic and are documented well in the product documentation. Typically you'd click black point on the darkest part of an image and white point on the lightest part, and it adjusts the curves for that particular image. I don't use them. They yield linear curves which usually clip the image. I just adjust the R G & B curves by hand as per my article:
http://starmatt.com/articles/curves.html

In that article, figure 3b is what you get with black point and white point. Figure 3a is what you can easily achieve by hand.
--
Matt BenDaniel
matt@starmatt.com
http://starmatt.com


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