Say you’ve just gotten into wildlife video. One of the first questions is, what should your project’s final framerate be? Or in other words, what’s the best output framerate? The most common framerates on Youtube are 24, 25, 30, 48, 50, 60. The reason why there are values that are close together like 24 and 25 is locale dependent because places with 50Hz power use the 25 as a standard. If you are producing DVDs or something for broadcast television, then the difference between 24 and 25 matters, but here I’ll just be talking about Youtube or online video. So let’s simplify the choices between 24, 30, and 60. (But feel free to replace 24 by 25, 60 by 50).
I’ll give you the short answer: 30fps is best for most people.
But now let’s talk about why. First, it’s true that motion will appear smoother at higher framerates, so you might think 60fps is best. This makes sense. However, a lot of cameras can shoot at 60fps, but can’t shoot any higher, especially at in 4K. So, if you want to use slow motion, you can’t do that if your camera can only shoot up to 60fps and your project is also 60fps. Whereas, if your project is at 30fps, you can at least do 2x slow motion. 30fps still looks decently smooth, so it’s not that much of a compromise. Now, if your camera can do 120fps and you want to have the final product at 60fps, it will also look very good. Or if you never use slow motion, you could always shoot at 60fps and have the final project use 60fps.
In conclusion 30fps still looks smooth on its own and gives a lot of flexible options for slow motion.
Now what about 24fps? Virtually all movies are done in 24fps. That’s pretty much every movie coming out of Hollywood. Well, I urge you to avoid 24fps like the plague. It can work for people who move slowly, and most people believe that the noticeable choppiness of 24fps adds to the “cinematic quality” of the film. However, even with humans, in action scenes, 24fps is noticeably choppy, and this gets even worse with fast-moving animals. So for nature documentaries, 24fps is a horrible framerate. (Personally, I have done experiments with watching movies slightly sped up to around 30fps and after watching a segment in 30fps, I find it very hard to go back to 24fps.)
Therefore, for wildlife documentaries, 30fps is a great compromise between a fast enough framerate for smoothness and a slow enough framerate so that you can still use a variety of slow motion effects. Again, if you have a camera that can film in 240fps then 60fps can make more sense for that ultra silky smoothness, but for most people with more modest cameras 30fps is a good choice.