How do I increase contrast of a texture

[gordonrobb]

OK guys, I've finished pulling my hair out (i.e. got none left )

I want a way to work with the contrast of a texture (mainly float texture).

I have worked out that it is the colorcorrect node I want, but I cannot for the life of me get the effect I'm looking for.

I want a way to take for example a black and white image and do things like increase the contrast, or make the darkest and lightest shades Black and White.

I am using the dirt node, and love it, but I want the dark bits to be black and the light bits to be white.

Can someone give me a blow by blow of how to actually use the colorcorrect node to achieve this?

[gordonrobb]

Does no-one know the answer to this? How do I ask the question directly of Otoy?

[roeland]

I want a way to take for example a black and white image and do things like increase the contrast, or make the darkest and lightest shades Black and White.

You have to decrease the Black level and increase the brightness scale.

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Roeland

[gordonrobb]

Thanks Roeland, I shall take a look at that.

Can I confirm then that the Black Level is moving the darks towards black, and the Brightness Scale is moving the whites towards Wite?

[roeland]

Yes that's how it works.

This is what the brightness and black point controls do when viewed as a curve:

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Roeland