7 Replies Latest reply on Dec 21, 2009 5:43 PM by the_wine_snob

# Time Stretch / Slow Motion Percentages

When doing slo-mo (aka Time Stretch), are there "magic" percentages that will give you better results?

For example, if I have a 2 second clip, will stretching it to an "even" multiple like 4 seconds give me a better result than, say, stretching it to something random like 3.75 or 5.32 seconds?

• ###### 1. Re: Time Stretch / Slow Motion Percentages

Not really. Although stretching it too much can make the playback a little more stuttery.

Although you can ease some of that by right-clicking on the clip and applying Frame Blend.

• ###### 2. Re: Time Stretch / Slow Motion Percentages

OK, thanks. That might be what I did wrong - stretching too much.

I did do the Frame Blend to all my slo-mo's (at least I think I did) but some of them were noticeably smoother than others.

(ETA: Don't know if you guys care about those "Correct Answer" things but I tried doing that and got a "Unexpected Error Occurred". As opposed to an Expected Error? )

• ###### 3. Re: Time Stretch / Slow Motion Percentages

Ed.Mache

From what I have heard there are "magic" numbers that most instructors advise their students to use in this regard. The following is an exerpt of how I answered a similar question elsewhere:

"Advised Slow Motion Speed" sets are given as:
50%, 33.33%, 25%, 20%, 16.67%
"Advised Fast Motion Speed" set are given as:
100%, 200%, 300%, 400%, 500%

What is looked at is the even manner in which the frames are added or removed. And, the decision is based on the speed change percentage. In the case of the 50% speed set, the ratio would be 1:2, reflecting that every one frame ends up as two; 33.33% speed set, the ratio would be 1:3, reflecting that every one frame ends up as three, etc. In the case of 200%, the ratio would be 2:1, reflecting that every 2 frames become 1, etc.

It all goes to the smoothness of the motion.

ATR

• ###### 4. Re: Time Stretch / Slow Motion Percentages

ATR,

That makes sense, actually.

I'll try these on my next project, and see if it makes a difference on my slo-mo's.

Between that and not over-extending the length, maybe I can get them looking a little better.

Thanks!

• ###### 5. Re: Time Stretch / Slow Motion Percentages

ATR,

Thank you for posting those "magic numbers." I have been looking for them, since I saw Ed's post, but you beat me to the results.

Much appreciated,

Hunt

• ###### 6. Re: Time Stretch / Slow Motion Percentages

Hunt

I have been very busy and have not been able to visit here as often as I would like. But when I saw this thread and saw that it needed a little bit more discussion, I could not resist.

Recently I have had a lot of slow motion and fast motion questions thrown in my direction. So I have been doing a lot of homework, exploration, and experimentation on the topic. At one point we even got into "ramped slow motion". A YouTube video tutorial helped on that one.

ATR

• ###### 7. Re: Time Stretch / Slow Motion Percentages
I could not resist.

We all benefit, when you yield to temptation!

Thanks for dropping by with some good input, as always.

BTW - Merry Christmas and Happy Holidays,

Hunt