Depth dependent opacity?

AndyS

Hi,

my question is related to the natural behaviour of water.
The topics reflection and refraction are handled very well.
But we all know the effect, when wer're in the water, our limbs seem to disappear the deeper they are. This is due to to the murky water.
The deeper an object is below the surface, the less light comes back.
So it seems that the opacity increases with increasing depth.

How is it possible to implement this effect in DAZ?

OK, you can install a lot of planes each inch under the surface with an specific opacity. But this is a very poor workaround.

Any ideas?

Andy

Richard Haseltine

You could also try using an uberVolume applied to a cube under the surface of the water.

AndyS

Hi Richard,

thank you for the answer.
What is Ubervolume? Can't find it in my content.

Could you please give some more information, on how this should be implemented to produce the result, I got in that example? That was produced as described in my intrducing post.

Andy

Szark

Content Library Pane (not Smart Content) > Daz Studio Formats > My Daz 3D Library > Shader Presets > omnifreaker > Uber Volume

Create a Daz primitive (cube) select the cube, select the surface and apply the Uber Volume. There is a Help link preset which directs you to http://www.omnifreaker.com/index.php?title=UberVolume

Lissa_xyz

FirstBastion's Breaking Waves product is also nice to use for this. It has the waves in both normal and subd and comes with a dark depth object w/ it's own shader.

Here are images w/ the dark depth object on and off. First is OFF, second is ON. Rendered w/ the default lights that come with it.

AndyS

Hm,

so far, it seems that I understood how to implement that dusty material. But at the moment it only creates a dusty cone starting at the origin, where my primary light source (distant light as the sun) resides. And I ever need an extra light source to let it start. :smirk:
But what I need is a dusty medium filling all the space evenly below the water surface. How to get this?
What Vaskania showed looks interesting. But I don't want to extra purchase the "Breaking Waves" only for that effect.
The question is: How was that effect created? How to implement only that effect into any scene?

mjc1016

smftrsd72 said:

Hm,

so far, it seems that I understood how to implement that dusty material. But at the moment it only creates a dusty cone starting at the origin, where my primary light source (distant light as the sun) resides. And I ever need an extra light source to let it start. :smirk:
But what I need is a dusty medium filling all the space evenly below the water surface. How to get this?
What Vaskania showed looks interesting. But I don't want to extra purchase the "Breaking Waves" only for that effect.
The question is: How was that effect created? How to implement only that effect into any scene?

There's a bit of a learning curve to using the UberVolume...best advice, keep playing around with the presets/settings, until you get something you like then save that out as new preset (File > Save As > Shader Preset). Then you can apply it to a cube, instead of a cone.

AndyS

Ähm,

at the moment I don't know what you're talking about.
Using the shaders of omnifreaker the only way is to apply a dust cone or sphere as the source to a light device.
This is the only instruction I found in the specified tutorial.
How shall I create a pure dust device which can be applied to the inside of a cube?

Szark

Load a Cube Primitive from the Create Menu
Select the Cube
Select the Surface
Double click a base volume preset (without geometry)
Make sure you have a light or lights in the scene and test render.
Adjust one Uber Volume setting in the surfaces pane and test
return the adjustment and try another and test render again etc etc
This is the only why you will learn what each setting does.

mjc1016

Once you have the settings you want, make sure the cone is selected, in the scene AND select its surface, in Surfaces tab. Then go to Fille > Save As > Shader Preset.

This will create a preset for UberVolume that can be applied to any thing...and it will save the settings you just came up with.

AndyS

Yes, you're right.

Sometimes it is better not to follow the tutorials. :roll:
It is really that easy, what I found out by myself too, before reading your reply.

After I selected the surface tool for my cube, I simply double clicked on the "!UberVolume Dust" shader. That was all. ;-P
The only trick was to do it with the surface tool active.

Why aren't these simple descriptions available in the tutorials. :smirk:

Attached you see the difference between almost clear and murky water (including reflection and refraction effects).