Caching the final gather and rendering the image passes

…We can really soak up a lot of time in…rendering, but we have a couple of ways to optimize.…We've already optimized by limiting down the final gathered distance.…So that final gather is calculated at or under a certain radius.…There's one more trick though.…Caching the final gather which can really help in some situations.…In this scene, in camera two, we have a limited camera motion.…When I play forward on this, we can see the camera…does a slow dolly in and a bit of a nodal pan.…Because that frame doesn't change drastically…and because the only animation in here…is the camera moving, it's a good candidate for caching the final gather.…

What this lets us do is render that final gather once and recall it for each frame.…As long as there's not a drastic change in…what the camera is seeing, this will work nicely.…So it's ideally suited for shots like this,…where we have a dolly in for example.…What I'll do is to go into the…Render Settings, and into the Indirect Lighting tab.…Under Final Gathering Map, I'm going to add…