When I apply the effect "Speed" and raise it, it doesn't change anything. I'm using Hitfilm 4 Express (I think that might be the cause). Is it keyframe-incompatible or is it some bug?
Nope, it works fine in Express. I just tested it. Turn Keyframes on in the Speed Effect and set the value to 4.0. Move forward a few seconds and set another Keyframe at speed 0, then forward again to another Keyframe set to 1.0.It'll start fast, slow to nothing, then back to normal speed. The length will change accordingly.
General speed changes are far simpler if you just right-click the layer and select Speed/Duration, as opposed to using the video-only Speed effect, from the Effects panel.
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