Framerate and speed conversions

[Christoffer Glans]

I'm trying to calculate the speed of a clip so I can return a 25 fps clip to 30 fps which it was shot in. In Premiere and Avid there's a base-speed of 100 (percent) and I'm not sure if my math is correct.

30 / 25 = 1,2

Therefore, I set the new speed on 120. But when doing so I get the lost frames and problems you get with a speed that isn't correct towards the base time. So what is going on?

 

[Sabovic Adis]

What's the clip lenght (sec) in a:
- 25 fps project
- 30 fps project

Same or different?