Explanation: This menu offers the choice between two color spaces:
- sRGB (default): This is the worldwide standard with 256 levels of brightness for each of the basic colors red, green, blue, for displaying images on computer monitors.
- Adobe RGB: A color space developed by Adobe for broader color range of printed images.
As for sRGB all colors will be stored with shares of red, green and blue with 256 levels of gradation, the difference is that the maximum saturations are higher.
But using this color space has its traps: If pictures taken as AdobeRGB are displayed by software that does not handle color spaces correctly you will get fainter colors than with sRGB!
The color space is relevant only for creation of JPG-files, not for the RAW format.
Tips: Use sRGB. sRGB is a worldwide standard for digital photography and printing. Adobe RGB offers theoretically a broader range of colors but has the risk of not being processed correctly in your software or in the printing lab and can then produce worse results.
So you should think of using Adobe RGB only if you can control the whole processing chain until the final printing, are familiar with color spaces and profiles and have convinced yourself that the theoretically existing broader range of colors gives you visible advantages. There are lots of discussions and different opinions about the latter.
In a nutshell: If you have to think first which color space is the right one for you, stay with sRGB.