The 2 ways to get a Render Gamma compensated

Theory
Each image must be corrected with a curve called ‘Gamma’, in order to reproduce the eye behavior
This compensation is automatic in real cameras, mobiles, tablets: we need to do the same in our renders.

In V-Ray the gamma compensation can be implemented in 2 ways:
Adding Gamma Saving the image – OR – Baking Gamma during the Rendering

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(*) Starting a new project in Max 2014 or sup., Gamma works fine by default
It’s not necessary, but if you want to know more on this topic, check the lesson “All About Gamma”

Important

Your file must be fit exactly in one of these 2 combinations
Every solution must produce the same result
If you have a problem, you’re probably accidentally mixing these configurations

GAMMA SAVED – (Default setting from 3ds Max 2014 + V-Ray 3)
We call it “Gamma saved” because of Gamma is added during the saving:

Fix your scene according to AutoGamma model:

1. to be sure that gamma is added while saving, type fileoutgamma=2.2, then press enter
2. Color mapping only (no Gamma)
3. sRBG button – enabled
4. Always use the default option

GAMMA BAKED, also called Gamma 1.0
because of no Gamma is added during the saving, in fact it’s added rendering:

Fix your scene according to Gamma Baked model:

1. to be sure that gamma isn’t added while saving, type fileoutgamma=1.0, then press enter
2. Color mapping and Gamma
3. sRBG button – disabled
4. Always use the default option

(**)  IMPORTANT   Some Learnvray’s files have been saved in Gamma baked, some other in Autogamma
If a mismatch warning appears – JUST –> “ADOPT the FILE’S GAMMA”