Excluding fog from alpha and z-depth pass?

[Franx]

Like said in the title, how can I get an alpha and z-depth pass without the environment fog blended into them?

[svetlozar.draganov]

There isn't a option to remove the Fog contribution from the alpha and z-depth passes but there is one trick that may get you what you want without having to render the image twice (with and without fog). It's possible to export deep and non-deep .exr files from V-Ray simultaneously using V-Ray ray Image File option and Separate Render Channels option:


The non-deep exr file will be written with fog contribution over alpha and z-depth elements but the deep .exr file will not have that contribution.

[LarsSonparsson]

What about rendering Falloff Map as an ExtraTex render element?
Set the Falloff Map to distance blend and set distance parameters as you would in z-depth.

[Franx]

Great, thanks for the tips guys.

[thanulee]

What about rendering Falloff Map as an ExtraTex render element?
Set the Falloff Map to distance blend and set distance parameters as you would in z-depth.

Does this produces same results as z? ty