Animation Autoexposure

[David Nisbet]

I've been testing several setups for interior animation and I'm having a difficult time with lighting remaining consistent from one frame to the next which produces an incredibly disturbing light flicker. I've also noticed that even though I uncheck the autoexposure box, render, stop render after a few frames have run, then the box is automatically checked again.

Therefore, I think the source of my flicker is the autoexposure recalculating every frame. Is there a way to keep this off? Evidently unchecking the box doesn't seem to work.

Thanks,

David

[Roy Hirshkowitz]

Definitely not tone op flicker.  The autoexposure checkbox is probably working just fine.  

Interior daylight animations are particularly difficult-- we don't have a lot of people doing these-- and I haven't put a lot of effort into stabilizing them.  It may stabilize a bit more if you can stand more passes/frame.  How many passes were used?

 

Just for grins you might also consider panoramic renderings as an alternative.

[David Nisbet]

Three diferent attempts with passes at 15, 25, and 50.  The one I posted was the 25 passes benchmark but each one had very similar results.  I have also started playing with the slideshow and initial tests yield more stable results.  I'll post a sample file so you can see what I'm talking about. 

 

I am trying to put together a cost estimate for a client who wishes to see an interior animation of 4 different spaces inside the building.  My approach is to do some broad sweeping pans of each space and cut them together with transistions.  This will be easy enough so long as I can do the animated sequences without the sudden changes in lighting.  Any thoughts as to whether or not the lighting issue can be resolved?

 

Thanks for your input.

 

David

[David Nisbet]

Slideshow draft

[Roy Hirshkowitz]

Not easily-- but it may be worth a try if you have time to experiment a little.  

First my (untested) theory-- the daylight portals are unstable due to some optimizations I added.

The only way currently to defeat this is to use daylight sources in a limited way.  For example-- in Advanced Lighting turn off AutoDaylight sources.  Try a test rendering and see if the instability goes away.  If so, you may be able to manually tag only the most important surfaces as daylight portals-- in your case, the large windows in the main space.  Let me know if you have any success (I'd be very interested in seeing any intermediate results you care to share.)

 

I still think panos are a better bet for this sort of thing.  You might want to run one or two by your client to see if he'll bite.

 

[OndraZ]

We experience same thing (flicekring) also in sun study - see atachment.

[Roy Hirshkowitz]

We should be able to get exterior sun studies more stable than this.  Is there an exposure lock switch in there (and did you use it?)  Interior sun studies are very problematic.

[OndraZ]

I think that in sun study there isn't such a switch for exposure control of frames...

[Roy Hirshkowitz]

I'll check and add one soon if it's not there.