VRay light fog effect, partial loss of lighting

Just like in the picture, I added many lights and then added environment fog, but there was a problem of partial loss of light fog effect during rendering。The demonstration video and engineering file of the problem I uploaded


video.rar (3.21 MB)
file.rar (77.7 KB)

Hi 123456_​,

Thank you for sharing your scene. To achieve better result, I recommend increasing the Max Subdivs - setting this parameter back to the default value.
Additionally, you can try the following adjustments:

Please try these adjustments and see if they resolve the issue. If the results are still not as expected, could you please share your Cinema 4D and V-Ray versions?

I found that changing to the options in the image would prevent rendering errors, but the rendering speed would be very slow. Could it be an issue with adaptive lighting? ![YP(3AH6]~1[quote=“zhanet.georgieva, post:2, topic:120670, username:zhanet.georgieva”]
Hi 123456_​,

Thank you for sharing your scene. To achieve better result, I recommend increasing the Max Subdivs - setting this parameter back to the default value.
Additionally, you can try the following adjustments:

Please try these adjustments and see if they resolve the issue. If the results are still not as expected, could you please share your Cinema 4D and V-Ray versions?

[/quote]

I found that changing to the options in the image would prevent rendering errors, but the rendering speed would be very slow. Could it be an issue with adaptive lighting? C[quote=“zhanet.georgieva, post:2, topic:120670, username:zhanet.georgieva”]
Hi 123456_​,

Thank you for sharing your scene. To achieve better result, I recommend increasing the Max Subdivs - setting this parameter back to the default value.
Additionally, you can try the following adjustments:

Please try these adjustments and see if they resolve the issue. If the results are still not as expected, could you please share your Cinema 4D and V-Ray versions?

[/quote]

I found that changing to the options in the image would prevent rendering errors, but the rendering speed would be very slow. Could it be an issue with adaptive lighting? S127QI[]5R.png|801x259](upload://yZuJlAU8tAPv27gQQgyVlTbtAY5.png)

Hi 123456_​,

From your settings, I noticed that the mode is currently set to Adaptive Lights, with the number of lights set to 8. This low value can lead to artifacts in the render, as you’ve observed. To achieve correct results, I recommend increasing the number of lights.

Alternatively, you can switch to Full Evaluation mode, which provides the most accurate lighting calculation. However, as you correctly mentioned, this mode will significantly increase render times.

It’s important to note that improving render quality generally requires higher settings, which naturally impacts render time.

Thank you for your answer