What is the relationship between hue, saturation and value?

Question

I see people adding color on top of a gray-scale drawing and their colors look great, but when I do myself, the colors look terrible (dirty, not the color I seem to pick from the color wheel). People tell me I need to learn about tone and value and the color wheel. I've gathered from this site and others that tone is really hue, which is really what we call color. But I'm not sure how saturation and value work into this.

What is the relationship between hue, saturation, and value and how does this factor in to coloring a gray-scale picture?

And even a good explanation of the color wheel would probably help. Thanks.

Answer 1

Value is essentially the darkness of the pigment. Less value equates to a darker color. If you take a color and remove all hue, you are left with value - basically greyscale. Brightness is another term used for value. Often brightness is a bit easier to remember since more value means a "brighter" color.

Basic Value scale

Saturation is essentially the depth of the pigment. More saturation means more pigment. Less saturation equates to a tint or lighter shade of the color. Luminosity is another term used for Saturation.

Basic saturation scale. (based on a red hue)

Hue is the base pigment.

Basic Hue scale

"Color" would actually be the combination of all three of the above.

For example if you have a Hue which is red.

• Decreasing Saturation/Luminosity will cause the red to start moving into the pink areas. Hue minus Saturation = lighter color
• Decreasing Value/Brightness will cause the red to move into the maroon or burgundy range. Hue minus Value = darker color

Anther way to think of the relationship is to consider removing Saturation as adding white to the hue. And removing Value as adding black to the hue.

If you are coloring a greyscale image, you would use the greyscale to designate the value of the colors. To that end you would never adjust the value of the color you are using allowing the underlying greyscale tones to create darkness. You would choose a hue and a saturation, then paint over an greyscale area, setting the blending mode to Multiply or Darken to allow what you are painting to interact with the underlying image. Because you are using a base greyscale image, you would never want to create an area which is lighter than the image. The only variation would be how much color is applied, thus hue for the pigment value and saturation for the amount of pigment.

Answer 2

Hue: what color is it? Saturation: how much is it? Value: How dark or white is it?

If Hue is Red, and saturation is 100% then it is a different color then if Hue is Red and saturation is let's say 60%/99%/01% etc, so for the value. There is Dark Red, and so there is Light Red. As things lose Saturation, their 'lightness' is converted from color to equivalent gray/white 'lightness'.

Answer 3

Hue: the wavelength of the color (at what angle does it fall on the wheel)

Value: the lightness/darkness: tint (lighter) or shade (darker).

Saturation: describes how pure/intense/strong the hue is.

Pure Magenta = 100% Saturation

Pure Magenta + 4 drops of white = Magenta Tint

Pure Magenta + 2 drops of Cyan + 2 drops of Yellow = Magenta Shade (adding cyan and yellow to magenta is like adding black because it's the complement to magenta aka green)

Pure Magenta + 2 drops of white + 1 drop of cyan + 1 drop of yellow = Muddy Magenta

The Magenta Tint, Magenta Shade and Muddy Magenta all have the same amount of decreased saturation (from the Pure Magenta) because you diluted each of them by the same amount (4 drops total) but the Muddy Magenta has the same Value as the Pure Magenta because adding white and black (cyan&yellow) at the same time correct any change in value.

Magenta Tint (lighter value and less saturation)

Magenta Shade (darker value and less saturation)

Pure Magenta value = Muddy Magenta value (same value but Muddy Magenta has less saturation than Pure Magenta like the Magenta Tint and Magenta Shade)

Answer 4

I liked the answer by @Scott. If I understood his answer well, then I try to explain Hue, Value, and Saturation based on physics.

I think the Hue corresponds to the wavelength of light. This is a property of light and not the object that light is illuminating.

Then the Value corresponds to how much the light is absorbed by the object it is shining on. If an object absorbs all the light shinning on it, for example a red light, then that object looks dark and if it does not absorb at all the object looks red (if we use a red light of course). This is the property of the object's surface and does not depend on the light source.

The Saturation corresponds to how much the light is scattered upon shinning on an object (how it is reflected). This is also a property of the object's surface. If the light is scattered %100 the object looks white regardless of the wavelength of the light. If the object does not scatter and reflect the light perfectly, then assuming we use a red light and no absorption, the object looks red.

For summary, suppose we use a red light source. The object has two properties, those are how much the object absorb the red light and how well it reflects the light perfectly (or how bad it scatters the light). If the object does not scatter the red light then depending on how much the object absorb the red light the object can look dark (perfect absorption) or red (no absorption).

Here is the color picker from Photoshop and the axes that I think corresponds to the absorption and scattering.

Answer 5

There is a real confusion with saturation vs value or brightness. Tints and shades change both saturation and brightness. fully saturated color has a variety of value from yellow to blue- light to dark