Material Interpolation - Why?

[jujubee]

I understand it's supposed to speed things up. However, I had a scene with over 20 glossies and 'Use Interpolation' set in all of them. It took a hi-resolution scene over 12 hours to render. Disabling this on all of them knocked it down to abour 3 hours.

By leaving interpolation checked, am I effectively bottle-necking memory usage??? Btw, program reboot is deemed necessary after letting it cook that long...

[thablanch]

In my situation, use interpolation drops the render time at least by 2. Mostly for my part 2 glossies but everywhere...
I would guess that your interpolation is just cranked to high?

[jujubee]

It's default on the materials.

[percydaman]

well like just about everything now, default is just too high. I NEVER use interpolation anymore, just seems to not look as good and im not keen on the render times either.