Folks, please don't fart about with your (LCD) monitor's gamma setting. It was calibrated at the factory to be correct, and will take many years to significantly deviate from that ideal, if at all.

Your monitor's gamma settings may be labelled as 'Gamma 1', 'Gamma 2' etc. but these are just labels and have nothing to do with the actual gamma values they invoke. Somewhere in your monitor's user guide it will tell you what values the labels signify. You want the one that selects gamma = 2.2.

Monitors that can work in a truly linear fashion - i.e. where gamma = 1 - are pretty rare, and since I'm lucky enough to have one, I can tell you that the linear mode is useless for normal work. It's only used for hardware calibration. 

When I see another gamma question posted here my heart always sinks because all the usual guff will come to the surface. Over-complicated explanations and formulae, which may or may not contain useful facts, will be thrown around and pretty soon the answer to the original question is lost in a mire of gibberish.

Unfortunately, artbee, "why do I need gamma?" is a question that invites complicated answers. 

Better to ask, "Why would I want to use Gamma Correction?". The simple answer is that, as BB says, it takes the hard slog out of so many things. It makes things you do with lighting and shaders produce predictable, consistent, accurate results. You have to understand what it does and learn a few things, make some changes to your workflow, and that's about it.

Look at BB's images over the last few posts and you should be able to see why it's a good idea. That should motivate you to figure it out and use it properly.

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Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)

PoserPro 11 - Units: Metres

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