# How to do HSL or HSV operations in a texture?

• Say I want to do a RGB or CMY operation in a texture (say add a color); that's pretty simple with Add node.

Now, say that I want to a hue change, or a saturation change, or a luminance change in a texture. Is it possible to do it with the current nodes?

Say a pretty simple HSL operation, like set hue = 0, saturation = 0 and leave only luminance; that transforms a color texture in a grayscale texture. Is that possible to do?

Thanks!

• @fbs7 there are three nodes that do HSV (2 Poser nodes and 1 Cycles node) There might be more that I don't know about.

• HSV is basically the same operation as it would do in an image editor. Turning saturation to 0 does indeed turns the displaying of the texture to a grayscale.

• @fbs7 As @ghostship cited, you have three HSV nodes. The two Poser nodes differ in that one considers the input color hue to be the zero point, and the other sets it at 1. But yes, you can manipulate H, S, and V with these nodes, including setting saturation to zero to get a greyscale. Else, you could run the color into a math node (not color math), and you'd get greyscale output.

• Original HSV hue parameter is multiplied with the input hue. This why 1 is the neutral value or "unit" of the operation, as the unit of multiplication is 1.

HSV2 hue parameter is added to the input hue. This is why the 0 is the neutral value or "unit" of the operation, as the unit of addition is 0.

x * 1 = x
x + 0 = x

For both, the saturation is always multiplied (not added) and the value is multiplied (not added).

The original node was built to be uniformaly multiplication in all three parameters but users found that illogical, however consistent. So HSV2 was created to use add, multiply, multiply.

• Uuhhh... there hsv thingie really works - saturation and hue = 0 indeed make it a grayscale!

Wow, 10-15 years using poser and I never noticed that; I keep adjusting saturation of textures with external editors - never more!

Thanks all! By the way, what's the difference between hsv and hsv2?

• I wrote a thread somewhere about using the HSV (not HSV2) to directly change the color of foliage from summer to fall colors.

• I have a movie but it won't upload here even though it is only 2.2 MB and smaller than a lot of my screen shots. Oh well - sucks for you.