Tag Archives: compositing

“Três João” fishes VFX

“Três João” is a short student film from PUC-Rio’s Cinema college, in which I had the pleasure to contribute with visual effects for it’s last scene.

the scene required two goldenfishes jumping against each other in an open ocean,  filmed by the recording crew. they were sculpted in ZBrush, rendered with Arnold, composited in After-Effects and everything else done in Softimage.

Premultiplied vs Straight

As I was researching about the differences between these two color modes, I’ve noticed how many people have difficulty about it, most working with it everyday. So as a form of self study I made the following diagram.

{In a nut shell, when you have transparency in the Straight mode, only the alpha channel is affected, the RGB remains the same, pure; with Premultiplied, the RGB channels get multiplied by the background color, which most cases is black. The alpha channel of both are exactly the same.}

Click for a bigger version. Hope it helps ::