Need to create realistic pond water.

[Rens]

You can use mental ray shaders or the standard Maya shaders. Here's some info for when you're using the standard shader. I don't have Maya here at home and this is what I can explain best from the top of my head:

- For the reflections use a Sampler Info node. Connect the Facing Ratio to a Ramp node, to the V coord I think. Connect the Ramp to the reflectivity of your shader. The point of this is to create a falloff in the reflection that is dependant on the surface angle; a plastic bottle is more reflective on the sides than it is directly from the front. There are a lot of tutorials out there explaining this setup.
But just a standard linear ramp isn't correct, and this is what most tutorials don't mention, for realism you'll have to tweak the gradient (simple Fresnel).
Now this is from XSI but you'll get the idea:

http://www.rensheeren.com/images/cgtalk/IOR_15_BAR.jpg

http://www.rensheeren.com/images/cgtalk/IOR_15_SPH.jpg

That ramp produces that effect on a sphere when linked to the diffuse channel. The ramp for water should roughly go from 4% to 100%.

You'll have to do some google/cgtalk searching or experimenting for the correct settings for the reflections in your shader (not the ramp, but things like the specularity and refectivity sliders in Phong), I've found Maya not very intuitive when it comes to these settings.
If you want to go the experimenting route then don't use the ramp, just full reflections, reconnect the ramp later. I find getting the correct settings is easiest when you have a sphere on a plane and some coloured objects behind it.
When the environment around it is black the sphere should be black. When the env is white the sphere should be white and so on. Same with the colours. Don't use specular highlights at all, it doesn't make sense to use them when you have a smooth reflective surface.


- Transparency. The water in your example seems very muddy, you wouldn't see the bottom of the pond until you're very close to the edge. In this case you can probably get away with using no transparency and just using a dark brown diffuse colour. It'll surely save you on rendertime and it might actually look good, worth a try at least I'd say.


Hope this helps!

[Narratorway]

Okay, I'm confused. Are you saying the ramp should be attached to the diffuse, the reflectivity or both?

At first I couldn't get the thing to work at all until it occured to me I needed to use raytracing (i r bright person :P), but even then, the water looked too velvety. Does that mean the ramp has too much white or not enough? This is what I got so far:

http://www.neilpolenske.com/tempImages/progressReport02.jpg


http://www.neilpolenske.com/tempImages/progressReport01.jpg%5B/mg%5D%5Bimg%5Dhttp://studentsites.expression.edu/%7Enpolenske/oakeys/Locations/oakeysWater.jpg

[yencaray]

yes the ramp needs to go into the refectivity of the shader not the diffuse.... also the ramp will some-what be linked to your geometry so if your geometry and ramp is rather smooth so will the fresnel effect here that you are trying to simulate. Try changing the surface shading of it to be more of an overall flat surface with few small ripples for the pond....or maybe try shrinking the already made effect you have so that the surface noise going on it smaller and then go from there

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