[stanfordr]

Is anyone getting gibberish occasionally rendering (network or single node)? I am only getting small glimpse of the image, everything else is black. If I re-render the same scene, it renders fine without any changes.

[Fast Render Farm]

From where do you start the rendering? Cooperative mode?

[Mihai]

Any SSS materials in the scene?

[stanfordr]

It is difficult to reproduce because it seems random but I have had this happen on two separate models, one interior scene and one exterior scene. I am exporting my model from Revit into Maxwell Studio. Generally, rendering under Maxwell Network using cooperative mode but I have seen the same results when directly rendering from Studio and not using the network. Also, occasionally I outsource to a rendering farm (Pixel Plow) with the same results.

Also, I am not aware of any SSS materials in the scene most of the materials I use are basic or directly from Revit.

The only material that might be suspect is an AGS glass material set to 30% opacity/mask. (I use this as cover lens for my light fixtures in order to get my source of spot emitters to appear).

[Mihai]

Do you have very high emitter settings in your materials? Thousands of watts I mean. These black renders usually suggest that some values in the render have gone "out of range" and throws the whole render ouf of whack. About the lens covers maybe you can simplify your scene and possibly avoid some noise by just adding a custom alpha channel based on those cover objects. You can probably also set them to be hidden from global illumination. Then use the custom alpha to color those parts how you like in post.

[stanfordr]

I will try the custom alpha channel for the lens cover and hide its global illumination. Hopefully that will speed things up.

I still don't understand why a spot emitter is hidden but I'll post my results when I get a chance.

The scenes has 40 light sources, each at 900W @ 300.00 lm/W. Could it be the number of light fixtures?

Another detail that may or may not help is that as the SL increases the areas in black also increases. The initially preview only shows a few black lines but they continue to increase as it renders longer. Like I said, I if I cancel and re-render the same scene it will render out without any issues.