Xandi, how much light have you put on the scene? If you use the Linear 'camera' part of Lux, try lowering the exposure value. One possible culprit is that you have too much light hitting your materials.

If you're flummoxed by what I mean, you can also go into the light tab and lower the gain of the light, effectively taming the 'power output'. Your scene will darken, but you can counteract this by opening up the exposure which will let in more light. 

I'll try to get a screen grab of Lux  showing this in just a bit. 

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