Abstract implementation of tonal curves for RGB, Red, Green and Blue channels with three fixed nodes: highlights, midtones and shadows. Can be used to adjust overall contrast or create advanced color filters.
<img src="http://www.prr-art.com/things/construct/curves.gif" border="0">
Download Curves effect
Parameters:
- RGB Highlights : Positive values brighten overall highlights, negative values darken overall highlights.
- RGB Midtones : Positive values brighten overall midtones, negative values darken overall midtones.
- RGB Shadows : Positive values brighten overall shadows, negative values darken overall shadows.
- R Highlights : Positive values tint highlights red, negative values tint highlights cyan.
- R Midtones : Positive values tint midtones red, negative values tint midtones cyan.
- R Shadows : Positive values tint shadows red, negative values tint shadows cyan.
- G Highlights : Positive values tint highlights green, negative values tint highlights magenta.
- G Midtones : Positive values tint midtones green, negative values tint midtones magenta.
- G Shadows : Positive values tint shadows green, negative values tint shadows magenta.
- B Highlights : Positive values tint highlights blue, negative values tint highlights yellow.
- B Midtones : Positive values tint midtones blue, negative values tint midtones yellow.
- B Shadows : Positive values tint shadows blue, negative values tint shadows yellow.
Don't let the number of parameters scare you, it's simpler than it looks and it's very versatile.