Random "Dark" frames in animation

[redi]

We are experiencing random frames that are dark during an animation sequence of a bathroom. Currently the sequence is rendering on one machine, MAX 7, V-Ray 1.47.03, XP SP2. The IR Map and Light Cache are being rendered for every frame, and current settings are "single frame" for both, after trying all otrher options with the same result. You will notice that even the dark frames (images below) have variations within them. Any ideas?

We started off the normal route, rendering IR Map for every 10 frames, incremental add to map. This was rendered out on one machine, and then network rendered, with the same result. Now we are down to one machine (dual core Athlon x2 4200) with the same results.

All suggestions will be appreciated, as the deadline is Thursday.

[Da_elf]

that looks like its not accessing an irradiance map

[redi]

Looks like it, but why? The IR map is being calculated for each frame individually on a single frame basis, and is not pre-rendered.

[instinct]

What if you render the sequence in the farm, and re-render only the bad frames locally ? That´s how we do it mostly. If it doesnt render locally at all (without backburner) then i´d suggest sending the scene to chaos and let them take a look

Thorsten

[Clifton Santiago]

What you need to do is to render the IR pass with multi-frame incremental on just one computer about every 10th frame or so, and autosave it. Set the file to use this IR map, and then send it to backburner. As long as all the render slaves can see the irradiance map file on your network, you should not have this problem.

[RErender]

I had something similar on a scene recently. Problem was that at just a few frames I got tons of overbright warnings and a bad lightcache. Solution was to turn the LC samples down from 1000 to 600 or so, then the frame would render right.

never did figure out what made those frames different from the rest...