I tried to change the texture file color space from default (srgb) to linear srgb and voila the color of the rendered picture is pretty the same as in the photoshop. I think I missunderstand something with the linear workflow setup and I made a gamma-correction node (0.454...) after the jpg texture file while the default input profile was srgb.
I changed to this:use the default input color profile: srgb non-linear and remove the gamma-correction node from the jpg texture shading network. According to this the "default input color profile: srgb" means: I use non-floating jpg image as input files and maya convert its colors internally/automatically into the floating values range. Am I right?
(and I only have to use the gamma-correction with the colors from the maya color pickers?)
thank you