Shooting a music video, need some slow motion help please!

[ForwardLooker]

HI Everyone,

I've got a music video shoot comming up which about 40% of the footage will end up slow motion.

I understand that its better to film in 50i for slo mo's but I also want the normal speed shots in 25p.

So do i:

shoot the whole thing in 50i then convert the bits i want to 25p?

shot the bits i think i will slo mo in 50i and the bits i want normal at 25p?

or

or shoot each shot twice in 50i & 25p?

My dilema is if i change my mind about what i want to do with a shot, will converting a 50i shot to 25p look as good as filming in 25p? and if i film everything in 25p i want get the good slo mos.



thannks for any help

[Fletch78]

Unless you can say for sure what's going to be slowed down and what not, I'd recommend shooting completely in 50i. Higher shutter speeds would be better for the slowmo scenes but no so good for the normal shots (unless you're after the 'Gladiator/Saving Private Ryan' look). But from my experience, a shutter speed of 50 is enough for most slowmo shots.

You just can't get perfect slowmotion from 25p. Some may disagree, but I'm talking about nice slowmotion without the need of artificial interpolated frames. So you'd have to shoot the slowmotion scenes in 50i and deinterlace to 50p (to slow them down to 25p) anyway. This diminishes quality a little, but by shooting the rest of it in 50i and deinterlacing it to 25p you'll get exactly the same image quality for both the normal and the slowed down shots. And, as you say, you can always choose later.

BTW, I'm assuming you want to slow down to exactly 50%...anything else is not smooth.

[ForwardLooker]

thanks for that rapid response fletch78! thats definetly some useful info!!

[Ian-T]

I agree with everything Fletch said except I would double the shutter speed.

[ForwardLooker]

yeh ian-T i think uping the shutter is a good idea, I have searched around and it seems like the good slo mos have higher shutter.

fletch, how do i convert 50i to 50p? so if i slow it down 50% does that make it 25p?

[Fletch78]

yeh ian-T i think uping the shutter is a good idea, I have searched around and it seems like the good slo mos have higher shutter.

fletch, how do i convert 50i to 50p? so if i slow it down 50% does that make it 25p?

My method involves preparing the clips I need for slowmo and resaving them with an intermediate codec (I use the free Lagarith lossless codec), as I don't want to lose more quality. It may be a bit complicated, but I like to have clips already slowed down when editing (the NLE I use, Premiere Pro 2.0, is a bit 'dumb' in calculating slowmos anyway).

I use TMPGEnc 4.0 XPress (a very good and cheap allround converter) to convert 50i to 50p. I set the Deinterlacing mode to "Deinterlace always (double framerate)" and the deinterlacing method to "Interpolation - adjusted" (it keeps non moving parts sharp). Then I save the file as avi files with a 50 fps progressive framerate. Now you just have to slow the clip down to 50% in your NLE to get a smooth high quality slowmo shot in 25p.

I'm sure there are different methods, but I'm having great results with mine. And after all, I can really recommend TMPGEnc 4.0 XPress (no, I don't work for them...). It's very powerful though ridiculously cheap, you can make your own presets, it allows high quality filtering (good for flipping 35mm footage too) and can convert almost any format I can think of (HDV Mpeg2 as well).

[ForwardLooker]

hey Fletch, just tried your method with TMPGenc 4.0 XPress and it works a treat!!

So I'm gonna shoot the whole thin in 50i.

Thanks for the help guys.

[ForwardLooker]

it allows high quality filtering (good for flipping 35mm footage too)

Where can i find this?

EDIT: ok found it!

[CSB]

Sorry for bumping such an old thread, I have TMPGEnc Express and I've been trying to convert some 50i footage to 50p. I've used the settings mentioned by Fletch78 above but I've ended up with a huge (2.8gb) file from a 40mb source file from a hv30. the file is almost unplayable on my laptop, very jerky playback and it appears to be in 4:3 format after conversion.

Can anyone help please?