Anyone have suggestions how I can improve the attached render? The foreground seems way too dark for the lighting. The sun is coming from the left, there are no surface obstacles off camera to cast a shadow. I tried raising the sun from 25 to 30 with no effect. When I turn off the water and render the terrain, it seems to be getting direct light. So it has something to do with the water. I tried turning off the water shader and that didn't help so I think it has something to do with the water feature itself but I'm not sure what to change.
try to change the "Volume 1 Density" of the water.
you can find it in your "water shader", "Sub-surface" tab.
Thanks, Seth, I changed Volume 1 Density from 0 to .2, which turned the water green, I assume that's from the Decay Tint, so changed that to blue. It's looking better. Will work on it some more.
Decay Distance in the same tab will darken the water too. Increasing that will allow some light up from the seabed making the water look more tropical and shallow. Not sure if that's what you're looking for. If it is, it maybe worth moving the Decay Tint over towards the blue as well.
I'd say this looks pretty normal. You might want to either raise the ground beneath the water or, as Hetzen says, increase decay distance to see furthermore beneath it. If your water plane is very high above the ground you won't see much beneath the surface and it will appear very dark. You should check how far beneath your water surface the ground is, if it's too far for your decay distance then the water will appear near opaque.
Opaque water is fine. Something along the lines of:
http://www.moc.noaa.gov/mf/visitor/las/pics/Island.JPG (http://www.moc.noaa.gov/mf/visitor/las/pics/Island.JPG)
My lake's water level is 100. I have Decay Distance at 40 in a new render (will post soon),
Volume 1 density is .4, distance decay 40, decay tint is a light blue, also moved the sun up to 45.
The water in the photo is brighter because it is reflecting a brighter sky (lots of cloud), and the roughness might also help a bit. In your render you are reflecting a clear blue sky which is much darker.
Matt
Thanks, Matt, I'll add an upper layer of clouds.