CMYK color mode with 32 bit color depth requirement

[kyled84767719]

Hello, 

I have a photography project that requires the image to be in CMYK color mode with a 32 bit color depth. 

However, when I have the color mode set to CMYK, the 32 bit color depth option is grayed out. Am I doing something wrong?! Or is it never a option to have 32 bit color depth with CMYK color mode, and therefore this requiement is unattainable?

[D Fosse · Accepted solution]

That's not 32 bits per channel. It's 8+8+8+8=32.

[kyled84767719]

Thank you for clarifying! 

[Conrad_C]

This is a common point of confusion. To minimize confusion, when someone tells you a bit depth requirement, always ask to clarify whether they mean bits per channel or bits in total.

As another example, HDR is often edited using a 32 bits per channel file, which is relatively rare and new. But when some people hear it as “32-bit”, they say “It’s not new, I started editing 32-bit files in 1993.” But they are talking about 32 bits total (four 8-bit CMYK channels, or three 8-bit RGB channels plus an 8-bit alpha channel) while the HDR example is 32 bits per channel (RGB 32+32+32), or 96 bits total.

Leaving out the “per channel” means you can’t know from the number alone whether “32 bits” means RGB 32+32+32, RGB 8+8+8 plus alpha 8, CMYK 8+8+8+8, or some other combination of channels at other actual bit depths in other color modes.

[kyled84767719]

Thank you so much for your explanation on this! So helpful. 

[c.pfaffenbichler]

Please remember to marke the »Correct Answer«.