Water: reflective and semi-transparent

[skogzort]

Hello all,

I was hoping that someone may be able to help me achieve this affect:


water that is both reflective and semi-transparent/translucent. I have fallowed the threads on this topic and used the same settings that Valdo posted:


but, no matter how I play with the "thickness" or "fog multiplier" I cannot get any degree of transparency at all. I have tried making the water a plane and a volume but either way it is always rendered as just a reflective surface that you cannot see beneath. The scene is lit by one direct light and Vray sky. I have GI refractive caustics checked. I am new to using Vray so it is probably something obvious, but I'm out of ideas.

This is with no-water: (so you can see what you should see under the water)


This is what I get when I render: (with slight variation, but never any transparency)


Thanks much for any help

[winberg]

Try lowering your fog multiplier to something like 0.01 or maybe even lower...this depends on the scale of your scene..

-Tom

[dominiquelaksmana]

hi skogzort,
i don't know whether this will help, well anyway,
this is what i did
http://img254.imageshack.us/img254/7978/13en.jpg
http://img107.imageshack.us/img107/4420/22qs.jpg

[DaForce]

Its generally pretty easy to setup, but i found that scene scale plays a BIG part in wether or not it will work.

Try simple scaling your whole scene down to about 10% or so... and see what that does.

here is an old water test of mine... could work out ok.
Use to make a murky water... but since all the SSS changes im not sure if it does.

[skogzort]

Thanks for the responses, I’m glad to see that the Vray forum is still as active as I remember it

I used both of the settings that were provided, but they could not affect the “transparency” of the water. I have tried going from .001 to 1.0 with fog multiplier and .6 to 10,0000 on the thickness, but still no affect on the “Transparency” of the water. I tried scaling the scene up and down – it changed the color of the water, but still no affect on the “Transparency”.

For this test scene:
Display unit scale = feet w/ decimal inches
System unit: 1.0=1inch
The water is 3 feet deep and the boxes are 8 feet tall.
The direct light multiplier it at 1.0
The Vray sky is at 1.0
The geometry is all very low poly – Should I subdivide the water?
GI = 1.0 primary IRmap + 1.0 secondary QMC, refractive GI caustics is on but not reflective

Can anyone tell me if it is necessary to use a “volume/box” instead of a “plane” for the water geometry in this situation?
If you can get away with just a plane, should you have “two-sided” and “reflect on back” selected in the options?
If you do need to use a volume, then is it un-necessary to check “two-sided” and “reflect on back”?


Thanks again for the help,
I will continue to experiment and try everything that anyone suggests

[DaForce]

a plan "should" be fine, but you may as well try a box that has thickness... say as deep as the water.

If all else fails, but your scene and let one of us have a poke around.

[dominiquelaksmana]

yes i think it's a good idea to post the scene,
i mean if you need it urgently....

[trick]

Does the Direct Light use VRay Shadows ?

[armilla]

Hi skogzort,
I was just wondering if you ever managed to resolve this problem, as I'm currently experiencing similar issues and it's driving me mad trying to find a way round it. The water looks nice (based on DaForce's murky water settings), but I just can't get any transparency.

If anyone else has suggestions that haven't already been tried above, I'd very much welcome them.

Cheers,

Andrew.

[jonahhawk]

I know this is an old, old topic. for murky water, or water at all, I would not use Translucency. As I have experience that really only works if the object is back lit. Turn off translucency and play with the fog mult. The multiplier totally depends on the thicknes of the object. Make several boxes starting at 1 inch thick and going up to 3 feet thick. apply the same material to all. If you get what you want out of the thinner boxes but not the thicker ones then lower your fog mult.

Also when i'm adjusting the fog I like to set the ME sample size to something close to what I am applying the material to. If the stream or pond in this case is 3 feet deep, set the ME (material editor) sample (sphere or cube or whatever) size to 3 feet. that way you get better feedback sooner.