If you’re anything like me and you often find yourself flush with multiple green screen clips, the solution for a perfect key is not always clear. This is especially true when you either were not present for the filming or have multiple shots from different cameras and different angles that have to be smoothly edited together. Small things like lights being moved between shots, shooting on different days, a green screen not hung high or low enough, or the pesky errant object someone forgot to move off the set can lead to hours of frustration when it comes time to pull the key.
Almost all visual effects programs out there from Blender to the proprietary software of specialty effects studios offer the ability to key out green or blue screen footage for post-production enhancement. Personally, I find that I prefer two programs – After Effects and Fusion – to do the job quickly and efficiently (most of the time!). Fusion’s Ultrakeyer has saved me many times from a lengthy masking process and most of the time provides a decent color correction result all in the same tool, but, more often than not, I always seem to look to After Effects for my keying needs.
In After Effects, much like any other visual effects program, there is more than one way to pull a key. Color Key, Luma Key, and Keylight are just some of the base effects plug-ins that ship with the software, but ,when you add 3rd party offerings such as BCC Chroma Key from the Boris Continuum Complete suite or Primatte from Red Giant, things can begin to get a little overwhelming. Having tried just about every keyer I can get my hands on in the After Effects realm, I’ve come to the conclusion that the perfect key really depends on the clip and even clips from the same shoot may require completely different keyers to produce a desired result.
This keying flexibility has recently played a major role in the large amount of green screen footage that I have been working on for my independent film Choices. Due to weather, the availability of actors, and the lack of desired locations, we had to do more green screen shots than I would have liked, but, in the end, you just have to make it work as you can.
The process, thus far, has utilized Keylight, Primatte, and BCC Chroma Key to varying degrees with the results proving to be more than satisfactory. I have found that by creating effects combinations of Remove Grain, Saturation, Levels, Curves, and Colorama with the aforementioned keying plug-ins and saving them as animation presets in After Effects, the process can be streamlined to an extent. This approach of developing keying presets within After Effects has allowed me to focus more on the minor tweaking for each shot as well as the inevitable rotoscoping that always seems to come into play despite anyone’s best efforts.
So there really is no skeleton key that can pull or promise the perfect key for your green or blue screen footage, but taking the time to set up a few presets and making minor adjustments to them can really streamline the process and allow you to spend even more time with everybody’s favorite post-production nightmare – rotoscoping.