Building Light Cache Weirdness

[biochemical_animations]

I've built a scene where the light cache will calculate during render in about 20 seconds. Sometimes, randomly, after working with the scene, whether by using active shade for making changes or whatnot, I will go to production to render again, and the light cache will take a lot longer to calculate...like 3-5 minutes.

I usually stop the render and will powerdown my computer, reboot, open the exact same file that had the longer light cache calc, production render again and this time the LC calculates in 20 seconds...how it was built.

I'm using RT CUDA, and vray 35701.

Is there something I can check when the LC wigs out like this to see what might be causing this weirdness? TIA.

[vlado]

If you can get me the vraylog.txt file after this happens, it might contain some pointers.

Best regards,
Vlado

[biochemical_animations]

EDIT:

I just figured out what the problem is...I have a fade between two objects, one is fading out as the other is fading in...this is probably causing the LC to calculate longer...I was testing to see if I could do this in the max scene, but since the LC is taking longer, I'll probably instead do two renders and comp them in post.

I think the reason why my WS was rendering different was because it was getting a different frame from backburner than what I tested in single frame mode.

Sorry, for the mistake.

[vlado]

Ah, ok. Yes, comping the fades will probably be more successful. Let us know if there is anything else.

Best regards,
Vlado