I was watching a re-run of it on premium cable the other night, and wonder how much more difficult it was to film than a film with much less visual effects. Fake magics, lands, creatures, and other imagery that was never there to begin with --and live-action people acting out parts to things that aren't there. I know chroma key/green screen is used to add certain things to movies that will be computer generated, but when does one know to use an entire green screen environment, use green screen walls/materials in outside/real life environments --to mix and match what's being seen-- or use solely live-action people and real-life environments --like in some of the films earlier battle scenes?
The difficulty comes in with both how you have to film your principal photography, and then how much man power, equipment, and time it takes to craft and render all of the digital elements.
I don't think there's any quantifiable way to express how much "More Difficult" it is, you just have to learn what it takes and then compare that to how much work a less complicated film requires.
I
can tell you from my current experience creating a short with almost every shot requiring digital 3D effects, that it will take a lot out of you if you're working alone. Green screen photography will always be tricky, and getting the cleanest removal of the green (or blue) possible, including other exterior garbage around your actor from the background set and equipment, can take months of preparation, even with a large crew.
Then the task of designing and modeling all of the 3D environments and creatures takes a few more months, before the actual animation process happens. Then of course you have to add hair, leaves, plants, moss, feathers, tendrils, and what ever other small items hang off of these objects, not to mention digital rain, snow, dust, dirt, fire, water, and other particles. After which, now you have to light it with digital lighting that matches the live-action cinematography as close as possible. And finally the color grading process, which brings everything together with a cohesive color environment for each scene.
If you want to compare a 10 minute short with almost no effects to a 10 minute short with almost entirely effects, it's the difference between a few weeks in post production, to about half a year to a year in post production. That's the best straight answer I could give, because I'm going through exactly that. And my film isn't even as complex as it could be.
Because I knew I had to do visual FX for almost every shot in my film, I decided early that the only way that was going to be feasible was if I locked down the camera for every shot, so as to avoid needing to camera track anything, or deal with moving background elements that could have allowed the effects to look fake at any point. I also chose to shoot my film on flat, 90 degree angles rather than anything on a 45, or anything lower or higher than eye-line, because that also cut down on how many variations of the background extensions I would need to set up. I suppose it wouldn't take too much extra out of me, since my background environments are completely 3D and not static background paintings. But it still nonetheless will make things simpler in the long run. And I don't think anyone has really noticed the oddity of the flat angles. It simply gives the film a special "old-fashioned" style.
