Frank, what you do in vue when you say "input = 2.2" is the same as what you do in max when you set the "input to 2.2" in the gamma correction panel. In fact, the controls for gamma correction in vue are a clone of the ones in mental ray (I don't say that negatively btw, coherence is a very good thing)

Bruno, I attached a very simple image.
Gamma settings are following:

• display gamma = 2.2 (doesn't really matter, only influence what I see in vue)
• input gamma = 2.2
• output gamma = 2.2 (in order for the picture to be in the most commonly used color space on the web, srgb)

The cube on the left uses those settings
The cube on the right uses the exact same texture map (a radiant from black to white created in the Gimp and saved with a gamma of 2.2 (srgb in the Gimpt)). The only difference: on the second cube, I load the image with the override checked and load it with a gamma of one)

You can clearly see that the first cube is the correct one (in fact, you could push the test by creating a procedural gradient in vue and render it side by side with the two cubes - since procedural textures are mathematically calculated, they are always linear (unless you add a gamma node of course)