Why Rotoscoping Can Be the Most Helpful and the Most Hated VFX Technique
Didn't shoot on a green screen? Can't pull a good key? Then it's time for rotoscoping.
Rotoscoping is a tedious task. It requires hours of tracing over footage frame by frame to create a mask in order to separate unwanted elements from the shot. Usually you can avoid having to do it if you shoot on a green screen and are able to key out all of the stuff you don't want, but—if for some reason you were unable to do that, this video from Surfaced Studio will teach you how to rotoscope, as well as what steps you have to take in order to avoid having to do it altogether. ('Cause nobody got time fah dat.)
If you plan ahead before you shoot, you'll know which elements within the frame are troublesome, and can then plan to use a green screen for all of those unwanted elements so you can key them out later in post. However, if you don't have a green screen, rotoscoping is another option, one that can save your hide if something needs to be removed from your shot. But because it's extremely time-consuming, here are the tips from the video that tell you how to speed up that process, as well as make the final product look much better.
- Use a high shutter speed: Motion blur can make creating masks a pain in the neck. You can reduce motion blur by shooting at higher shutter speeds. (Make sure that the choice to shoot at a higher shutter speed doesn't interfere with the look of the rest of your film.)
- Use a lot of light: Good lighting can make rotoscoping easier, because light can separate foreground elements from the background. You'll need this separation when it comes time to draw your mask to create your alpha layer.
- Film necessary clean plates: A "clean plate" is a shot of a background with any unwanted elements removed, which is important if you're going to be adding VFX elements to it in post. This is one of the better tutorials on how to pull it off (with handheld footage, no less).
So, if you planned ahead and/or had access to a green screen, sweet! You don't have to spend hours upon hours putting in keyframes. But, if the whole green screen thing is a no-go for you, at least this video has shown you a few ways to make things run a little more smoothly while you rotoscope.
Source: Surfaced Studio