I also think it would be great for PD to have a bessier curve transition for speed changes, but there's actually a fairly simple way to do it by hand without any calculations and with only 2 speed steps.
For example, say you're working with 60p media and you want slow down one section to 1/3 speed. The quick way is to split the clip just before the point you want to slow down, then make another split 16 frames later and another one 16 frames after that (Do the splits at 8 frames if using 30p, etc).
Use the Power Tools button and set the speed of the first small section to 0.67x and set the second one to 0.48x (You can use any similar value, but these come up when using the slider). Finally set the main section to 0.32x. That's it!
If you return to real-time speed, do the same thing in reverse at the end, with the speed ramping back up briefly through 0.48x and 0.67x.
Here's what it looks like in a
video, and I think it's a pretty good approximation of a full curve but with a lot less work
YouTube/optodata
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