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Since the Linear Workflow matter borders with faith

and anyone seems to possess his own truth - while some live nicely without - I claim no paternity on what follows. This is just what the Chaos Group guy told us while I was working at TJ in 2011. Chaos Group guy, mind. It is then up to you.

1) Linear Workflow. Did someone ever provide a flow chart for a workflow? *facepalm* God bless my Asperger's and there it comes, neatly packaged a flow chart for Linear Workflow in Vray 1.5 running on 3DS Max. 
Stage one: it is Vray to cope with the whole Gamma 2.2 thing: turn OFF the gamma management in Max.
OFF. Even more: double check that the values for texture and material editor override are reset to 1. There is a nasty bug there that still processing textures even if the main gamma dialog is off. 
Stage two: the assumption is you are using the Vray VFB. Configure the Vray color mapping
rollover as following: crucial - gamma = 2.2, Linear Workflow = ON. Secondary - Don't affect colors = ON. Unimportant now the rest. Tadan! The mystical 'linear workflow' button on whose meaning everybody (even Vray manual itself °O° !) just glisses or throws in some dodgy ban. Well it is there and it does the whole job. Surprisingly it Can tell the sort of map is being processed (color, normal, hdr, bump) and adjust things accordingly. On the user side there is no need of loading maps with gamma overrides and plugins. You load everything in the plainest way. The so much abused 'Linear Workflow' button will do the sorting for you. Do you feel sorry for insulting it, now? :3 

2) Let's render. Get hold on the flowchart from above. We render in the VFB and we keep Don't affect colors = ON. Go read how cool is that. From now on we could output three different images. 
A) - a render preview to know what's going on. Linear rendering is damn cool yet a total eyesore. For preview purposes we just keep the sRGB button of the VFB down. Let's remind that if you work in linear workflow, as is, your images will look pretty dark. That solves it on the fly and for preview only. We don't save this stuff! 
B) - The final, production, correct output. The one that implies compositing and retouch will follow. Linear output gamma 1.0. The dark one we can't look at but that stores all of the precious color information we will need in Fusion, Photoshop and such.
C) - The preview mode to save on disk, or you stick with it if there is no retouch. Fundamentally wrong. Unretoucheable. But it looks normal. We get it by turning off Don't affect colors. In this mode we get in VFB the well lit image you expect in the end and you can save it and share it straight away. sRGB button is off now. You understand, though, this way the image has lost half of its potential. And other shit.

3) Compositing, editing, gamma restore. We continue, here, from the point B of the above chapter. We have one or more pretty ugly dark images in linear gamma. We keep them that way until we finish all of the compositing and any possible editing on them. Then, in very end, we will boost their gamma to the monitor friendly 2.2 value. How do we know how things are gonna look while retouching? Well, the software you'll use is supposed to give you some sort of preview mode that raises the gamma on screen. For instance:
- Photoshop - stack an 'Exposure' correction level (set Gamma 2.2)
on the top of your comp. Is floating. This move is in fact good 'till the very end, when you export the final image. Btw, Photoshop is a bloodbath for compositing; avoid it if you can. As if it wasn't enough it handles awfully the gamma thing (as well as HDRs); for instance I do compositing in Fusion even for prints.
- Fusion - connect a 'Color Gain' node at the very end your comp, set Gamma to 2.2 and render. For an on-screen preview of the footage
each window has a LUT button you configure and turn on (and off). Remember to apply all of your filters Before the final gamma boost! Raising the gamma here is like flattening a 32 bit TIFF to 8 bit and then to medium Jpeg!! You'll end up with just a shadow of the original image! It has to be done, but when any retouch is over.That's it :3 Of course if you use render passes in Vray there is nothing special to set up and anything works out of the box. Next tutorial will cover right that.