Photoshop barely works with 16bit images and of those features only some of them work in 32 bit everything only works in 8bit and even then you cant work in any sort of linear space. It's really sad that Photoshop which is supposed to be the king of 2d graphics cant add pixels together correctly, or even mulitply out an alpha channel. Let alone be consistent across the full range of bit depths they "support". I work with this kind of stuff everyday and have been following the development of Gimp and as slow as it is at least they have a plan and are working to it. Photoshop may have 32bit support by CS 21 at the rate they're going. One of their new features was a dark interface.. seriously.