How to Get More Environment Fog Contrast/Sharpness?

[mike_verta]

How can I get much more contrast and sharper shadow delineations with EnvironmentFog?

My single Rect light source is small. The fog density is 1 and transparency black. I'm controlling purely with distance.

Thanks much.

[damaggio]

You can enable directional in the settings or use a box hole off camera where the light passes thru.

[mike_verta]

"Directional" where? In the light? If so, that's already been done - the light is a narrow cone controlled by Directionality. And if it is already focusing the light, what is the advantage of passing the light through an aperture like a box hole?

[damaggio]

the box is to create sharper edges if you want it, other than that you can comp the atmospheric rays and punch up the contrast, Vray light beams are not very visible straight out of the camera.

[SonyBoy]

Not completely sure what you're shooting for... a tighter cone of visibly lit fog? Try creating a containing piece of geo (probably actually a cone) and limit the fog's influence to just that shape. This involves putting the geo into the fog's selection set. Reading the docs and a bit of trial and error should get you there (it's not always the most intuitive process). Normally it needs to be quite a bit larger than the actual light's cone to allow for falloff/penumbra.

[fixeighted]

I think the OP means stronger 'god rays', so increasing the 'affect atmosphere' would do that I believe....maybe....

[damaggio]

One think to keep in mind is that a denoiser will destroy your sharp light beams, see in the images...also the only way to sharpen the light and shadow beams is to use a directional light or a spotlight because you have the option
to control or fake the light/shadow sharpness, you'll have very little control with a Vray area light or a Maya area light because they are more accurate, specially the Vray area light.
Under Spot light and directional light you can control "Light Radius" which is fundamental.
Aside form that the rest is to punch it up by saving a Render Elements Atmospheric effects and comp in Screen mode.