I have noticed something with motion blur that I'm not sure is a bug ,something I am doing wrong , or just the way motion blur works.
Basically I have a very simple scene for an animation , and each frame renders out at 1500 samples in just 25 seconds :
However , If I turn motion blur on , it renders out just as fast until the progress bar reaches 97% , and then appears to freeze. However , it has not actually frozen , it is just slowed down. It then takes a further 2 minutes 43 secs to render out the one remaining tile that has the motion blur in it :
Now usually this wouldn't be an issue , but over a 375 frame animation it is adding 17 hours of render time just for the sake of motion blur.
So... could this be a bug or me doing something wrong? I recently rendered out a much more complex animation with a lot more motion blur on the screen and did not notice this happening.
Also , is there a way to composite motion blur so I can avoid these silly render times?
I played with the settings and discovered that turning down the shutter value helps decrease render time a lot , but at the cost of much less motion blur.
Hi Matthew, when your Frames look like the one above, you should use at least version 2.83 and enable Adaptive Sampling:
This will render the background with only 1 (or at most just a few) Samples and use 1500 Samples only where needed.
Also, if you enable the Vector Pass, you can use Vector Blur in Compositing.
A bit less quality than real Motion Blur, but a lot faster (haven't tried this myself...).
Brilliant Spikey thanks :) , is 2.83 stable yet as it is a big project I am working on?