Speed ramps and shutter speed

Dan Winckler

Hi everyone,

We are preparing to shoot an explainer video for a colleague that will have segments of sped-up motion. The (one) speaker will talk for a bit, then stick post-it notes on a sheet of glass in between her and the camera, then speak more, etc, and we'll speed up some of the post-it note sections in post. I'd like for the ramped sections to have a smooth, not herky-jerky feel -- smooth like ninjas, not frenetic like Buster Keaton. The project base rate is 24p and the ramped sections will be sped up by 2x or 3x. With that in mind, would you recommend either:

A) Shooting all of it with a 180° shutter

B) Shooting with a 180° shutter for the talking bits, then switching to a slow shutter (360°) for the to-be-ramped parts so they have more motion blur

C) Shooting with a 180° shutter for talking, then switching to a proportional shutter for the ramped parts, e.g., 24 x 2 = 48, hence a 1/96 shutter time 

D) One of the options above plus post-FX: if so, what would you recommend?

Based on my tests thus far, I'm leaning towards option B, but would welcome any advice from wiser heads and those who've shot something like this. Many thanks!


Dan Winckler
o: 347-867-8626 | c: 917-586-5213

Daniel Colmenares

Have you tried doing some tests at 60p, conforming to 24p for the normal sections, then ramping up to 60 for the slow down sections?

That might give you the smoothness you're looking for...that's assuming the normal and slow motion stuff happens in the same shot without a cut. Otherwise if there are cuts why not just shoot the regular stuff at 24 and the offspeed stuff at 60 (or 64fps if your camera allows those increments and you're dead set on exactly 3x)

Daniel Colmenares
Director of photography 
Los Angeles, CA