Slow Motion/shutter speed

[Alicia Ferrows]

i know slow motion has been discussed somewhat but its mainly been examples of what others have been able to achieve. Im here to ask what shutter speeds people are using to get good slow motion and if you are taking your footage into something like motion/after effects or doing it via your nle.

 

[Michael Carter]

Hmmm...

There's the DV (DVX) method of shooting 60i (interlaced) & transcoding to a progressive timeline, at specific speed percentages to get frame-for-frame slow motion. Yep, it's smooth as silk, but the drop in resolution (using interlaced frames vs. real frames) made it unusable for my tastes. Way too soft.

If you have a camera that shoots 60p - that's 60 full, real frames per second vs. 60i (interlaced) - you can transcode that to 24 or 30p and it's luscious.

My personal experience with the Canon 550d - it shoots 24 & 30p at 1080 res., and also shoots 720 resolution at 60 fps progressive. Pretty stunning, Cinema Tools takes about a half second to transcode it.

For shutter speeds, there are various "rules of thumb", mainly coming from our visual experience with slowmo from overcranked film cameras. A camera sped up to 48fps will give you 50% slowmo at projected speed - but a film camera running that fast has limitations in shutter speed that digital doesn't have. So to emulate "cinema" slowmo, you have a range of frame rates to stay within.

(Film guys, correct me if I'm wrong about that??)

Again, you wanted personal experience? For the 500d slowmo above, I tend to use shutter speeds of 1/40th to 1/120th. The main thing is to test and see what you like. If you're shooting in a controlled setting, shoot at several shutter speeds and decide in post what works for the scene.

 

[Ben_B]

Shoot 30p with a 1/60. Conform it to 24p for 25% slower speed. You can always try to slow it down more with pixel motion in After Effects or something. Anyway...general rule I follow is that you take the factor you're slowing it down by, multiply it by the framerate, and that gives you the approx shutter speed....plus or minus a bit. For 60p I shoot 1/120 for slowmotion.