Each image mode offers different capabilities of editing an image.
Therefore it can be important to choose the right one before applying special filters to an image.
Using the RGB channels
Besides the color information each channel provides us with it’s own specific characteristics.
These characteristics are used to apply specific filter effects.
Red Channel (Contrast):
The red channel can be called Contrast Channel.
It usually contains most contrast information and is used to apply selection operations.
Green Channel (Detail):
The green channel is called the Detail Channel.
Compared to red and blue pixel sensors there are twice as many green photosites on the camera. That’s because the cone cells of the human eye are more sensitive to yellowish-green light than other colors.
This channel provides the most detail information and is often used for B&W conversion.
The blue channel is called the Noise Channel.
It is usually the darkest and contains the most noise.
Therefore it is often used for noise reduction algorithms.
Using the Luminosity and Chroma channel
Converting an image to LAB color separates luminosity from color information channels.
L Channel (Luminosity)
It represents the B&W information of the image.
It is used to adjust lightness and sharpening operations without affecting the color information.
A & B Channels (Chroma)
The color information is stored in the A & B Channels.
Layer A represents the colors between green and red, layer B represents colors between blue and yellow.
It is used to remove color noise independent of lightness details.