what’s the difference in filming a video and speeding it up vs time lapse video?
In: 8
That depends on how you do it.
“Filming a video” is a very incomplete description. How many frames per second do you capture? How long do you expose each frame?
“Speeding it up” also is incomplete. Do you speed it up by showing more frames in the same timespan, or by dropping frames?
With the right answers to those two questions, there is no difference.
—
But that’s boring. So, let’s say you take a video at 60 fps and expose it at 180° (i.e. each frame for 1/120 second). To speed it up, you drop 59 out of every 60 frames.
The other guy makes a time-lapse video. He takes 1 frame every second and also exposes it for one 120th of a second.
The result is completely identical, only that you have a couple of GB of data to delete that the other guy never took.
Another example:
You do the same, but the other guy changes his exposure to half a second.
The result is quite different. The other guy has produced something you can not get from your material by dropping frames. And visually the results look quite different, too. Yours looks like it’s sped up (because it is), but his looks like it was taken at normal speed and everything moves very quickly.
The difference is motion blur. The sped-up footage had normal motion blur before it was sped-up, but after that, it only has 1/60th of it. That’s as good as having none at all. However, the timelapse footage has the same amount of motion blur it would have, if it was normal video of fast objects.
Third example:
You take the same video, but speed it up by showing it at 600 fps. You now have an ultra-high framerate video that looks very eery because it’s abnormally smooth. No matter who looks at it, there’s not the smallest hint of it being composed of frames left. The effect you get is that of a window instead of a monitor. Even worse than The Hobbit.
—
In summary, the difference is whatever you make it. You can get the same results or vastly different result, depending on the parameters you film with. After all, a time-lapse video is just a normal video that was taken with low fps and played at normal fps.
Latest Answers