Exposure Control Flickering

[zicher]

If you are using the standard exposure control (not the linear or the logarithmic), the flickering is normal.

I think the doc explains that the standard exposure control is not suitable for animations because it works on the average light of a frame. For a still it's fine, but in an animation each frame creates a different average and a different correction is applied.

If you are using Linear or Logarithmic, the flickering might be due to low quality settings for light tracer. Remember that light tracer works by random samples of the scene, and each frame generate different random samples creating slightly different results. Pump the number of rays up, increase the averaging and it should become less noticeable or disappear.

The Physical scale might affect it because of the presence of light emitting materials that increase their influence on the scene lighting when you increase the value. Read the doc to understand the Physical Scale. It's a value that need to be set correctly.

Rob

[Anton Andriesh]

thank you alot!... that heleped :applause:

but I haven't obtained a good result with Logarithmic or Linear exposure controls... the result is always too bright...

[zicher]

The way the exposure control works is nothing magic. It just reduces the internal color ranges (48 bits) to the 24 bits of most file formats.

This reduction can be done in a linear way or logarithmic.
Logarithmic is necessary for photometric lights and radiosity because of the extreme difference between light and shadow.

All photometric lights are physically based and have a square decay. While this is what happens in real life, it doesn't account for many other factors and the eye compensation for these differences.

If you are free to set up your ligts as you like, just apply the exposure control with default values, and then adjust the lights to get the best result.

If your lights are instead based on existing ones and can't be changed (like in an architectural interior), then you might have to adjust the exposure control parameters, but spend some time on the doc first to understand what they mean.

Rob

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