GI problem?

Started by bigben, July 11, 2017, 09:52:41 pm

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Quote from: KlausK on July 13, 2017, 08:10:26 pm
This issue is NOT related to rendering out sequences.
In my tests I tried sequences and single frame rendering.
Using the scene file bigben posted frames 1,2 and 3 are always dark (on my machine).
Frame 4 is the first which renders correctly here.
Hopefully the fix gets this.
cheers, Klaus

I had also experienced the issue with single frame renders AFTER it appeared in the sequence renders, with still renders matching the sequence renders, so there may have been a common tipping point. Both worked normally for me after rebooting. Klaus' specs are much better than mine so there may be something other than resources running out and the dark/light rendering matched my renders.


Yeah, I have to correct my earlier statement.
I deleted the animation from the camera and rendered single frames.
Except for the fact that the camera jumps to nowhere-land after deleting the animation
(I thought going to frame 1 would leave it in this position) the first frame  rendered "normal", meaning, with light green reflection.
Changing the camera position again, rendering, changing camera position, rendering and so on and so forth always got the render "normal".
Well, enough debugging, hopefully the "soon to be released update" is to be released soon  ::)
Cheers, Klaus
/ ASUS WS Mainboard / Dual XEON E5-2640v3 / 64GB RAM / NVIDIA GeForce GTX 1070 TI / Win7 Ultimate


Perhaps, but you should also be aware that there is always variability in the GI, even when things aren't animated. The lower your GI settings the higher the impact of this variability. Depending on settings, successive renders of the exact same settings can still have differences, usually minor enough not to be noticed, but in some cases not so minor unfortunately. Higher GI settings usually solve this, or GI caching where appropriate (yes, even useful for still-frame rendering).

Also, although you may be seeing some *correlation* between the issue and a reboot having an effect, it is unlikely that there is *causation*, this is probably just coincidence. I can't think of why a reboot would change this, there is always variability (randomness) in the GI calculation (as well as other calculations, e.g. AA/ray-traced sampling). In other words I don't think it's actually correlated to any resource issue, which should not affect rendering in this way. If you run out of resources, rendering either crashes or gets really slow, it doesn't slowly degrade, at least not through any mechanism I'm aware of. But maybe Matt has some more deep-knowledge thoughts about it. :D

- Oshyan


Photoshop filling the scratch disk... Windows Explorer failing to respond  = dark renders ;).  Probably killed a few other things along the way that impacted rendering.  Note to self... don't work on global source images while using TG.