I have always wondering how long does animated movies like Ice Age take to render? It must take at least 6 months…?
Those kinds of movies take a long time. If it were on computers like ours it probably would take six months for a frame. 
But places like dreamworks, and pixar have massive render farms that boost the project. Now if you take a movie like Lord Of The Rings. The render time for one frame of Treebeard was 48 hours( 2 Days), and that was how long it took for approximately every frame he was in for the film.
When you say one frame do you mean one keyframe? Like in Adobe Flash one keyframe would take 48 hours?
No, I mean one frame of film. And a movie that is playing at 24 Frames Per Second, and you think about how long that Treebeard is in that movie. It was a very long time rendering his animation sequences.
Indeed, although that was also ten years ago now (I still have trouble believing that) so nowadays they could probably render the same sequence in half the time, I’d say :yes: I’m basing this on the improvements seen between Blender 2.4x’s render engine and 2.5x, it was much faster and that was only after a year or so of development, IIRC.
Also, considering WETA Digital are insane (in a good way) they’ve probably found several new rendering tricks by now 
But, to answer CriticalError’s question, I’d say it depends on the film and the resources available to that studio. For the big guys, six months sounds a bit long to me, considering how fast Pixar and Dreamworks are pumping out 3Danimation-feature-lengths these days.
One thing to consider… is when talking about render times it’s spread among the computers… so 6 months of rendering spread across 6 computers = 1 month. It’s similar to man-hours in project management. A project could take 160 hours but be completed in a 40 hour work week with 4 people.
except instead of 6 computers rendering, they have 10’s of thousands of computers rendering
The glass building sequence in Transformers 3 took 288 hours per frame! And remember, that sequence was rendered on the worlds biggest renderfarm :eek: Source: http://en.wikipedia.org/wiki/Transformers:_Dark_of_the_Moon#Effects
Brecht would have to be a lot more than a good coder if we are to ever render be able to use today’s consumer hardware for something like that in Cycles, he would also have to be a magician (on a caliber even higher than Houdini), and then some.
I have read before that in the movie before that, the sequence with the Devastator almost literally fried the renderfarm at ILM (in other words it was almost to the point where rendering it was impossible with the current level of hardware technology).