I assume anyone who has used Indigo from iClone knows how long renders can take. Those who have top end machines are indeed blessed but I would bet even on those Indigo just about eats it alive. Here are some general observations about Indigo that may help someone or may not. Some I am not entirely sure about so anyone with better understanding of Indigo and IClone are welcome to add to this conversation.

1. Number Uno. Use Compositing. Never has film compositing been so important as with iClone-Indigo (if you're rendering animations, otherwise not I guess). It takes planning for such things but it can save a lot of grief if you can break a scene into one or more separate renders, which we can call "passes" just for convenience.

For example, let's assume there is a scene with a man going up to a door and ringing the doorbell. This is mid-distance with perhaps a few quick close-ups. The surroundings are objects from whatever source you derive scene decorations and maybe a few SpeedTrees (house front, sidewalk, grass, etc etc). This might not seem like a heavy scene load but it sure is when passed to Indigo. This scene amounts to, say, 15 seconds of film, or 450 frames. Give Indigo 2 mins per frame (1 min as suggested in one of Reallusion's tutorials is ok but not very good, why go to the effort if you can't shoot for better?).  Plan on having nothing else running on your PC. Go play solitaire or take that walk you need because it is going to take a really long time. 

If the scene is pretty static except for the man walking you can break this into two passes. In the first pass, you simply take the necessary "still" shots from every angle needed then use that as a backdrop when compositing. If there are realism tokens, like moving curtains or swaying trees or flickering lights, it may be necessary to pass those elements on with the render of the animated man, or if you're really good you can render such elements as a group in another pass. Once the background scenery has been taken care of, you can hide everything else in the scene except the man (if an object is required for his interaction, a dummy object could be used instead) and pass that along to Indigo. Here I recommend breaking the action into shorter segments -- it won't necessarily render faster but it will make compositing a little easier. Of course, check "make background transparent" in this latter pass. If everything has been handled correctly, which is why planning ahead is very important with this and isolating the right elements into the proper "pass", you can then composite the resulting renders into a whole clip. In this case, the animation of the man walking would be composited on the background stills. Note this still takes 900 minutes (plus overhead) to render, plus whatever is required for the stills, but the load on your PC will not be worrisome. I have tried this in an experimental way and it really does help. Passing a heavy scene to Indigo, even if short, brings my PC to its knees and at that point it all becomes vulnerable to a crash. Things seemed to go smoother using this technique.

I hope I'm not rushing in yelling "Hey, guys, the sky is BLUE!"  I never really did much compositing until these new render engines came in.

Perhaps Indigo should lease Blender's Cycle Render Engine technology -- if you haven't seen it work lately you will be blown away. I'd use Cycles for most rendering if it were more convenient to access through iClone. In terms of quality and speed of render, nothing out there can touch Cycles now.

I guess the main thrust of this is that you have to get smart when facing render times of days and find ways to 1) reduce the load; 2) reduce the complexity; 3) reduce recovery time in the event of an abnormal termination. While compositing may add some complexity, it can help with 1 and 3. There are many "movie" effects that depend on compositing and that can open a whole new area (which, of course, is why there are products like After Effects).

2. Test Render. I ran into some geometry issues with Indigo a while back in which models I brought in from elsewhere rendered horribly in Indigo. What was puzzling about it was the same scene rendered fine in iClone's native render engine. I spent (wasted) time trying to figure this one out and it appeared to be coming from some combination of bad normals or bad materials. Take your pick. I found a way around it but it is advisable even with iClone's native objects to do a test render before going to a lot trouble only to find Indigo trashes your centerpiece in the scene.


More later. Anyone interested in this is welcome to jump right in. I doubt I will ever be more than a student in this stuff.