Achieving true half-speed slow mo through HD-SD conversion
 

I've been pondering, is it possible to shoot footage in 1080i, then deinterlace to have two separate 540-lined fields, which can then be converted to SD progressive frames, thus creating half-speed motion but in SD?

The only problem I foresee here is that 540 lines is NTSC and I need PAL...

Hi Jonny and welcome to DVinfo! I guess it depends on your software, but suspect you'll get something very close to what you describe by slowing down your 1080i footage 50% in your NLE, then downconverting the results to standard definition.

So it'll definitely render each field as one progressive frame?

I'll be using Sony Vegas no doubt, if I were ever to edit any HD (initially)... would it work in this?

Thanks :)
Jonny

Jonny: I've moved your thread to our Vegas forum since that's a better place to get an answer. I'm on the Mac myself...

okay, thanks

Super Smooth Slow Motion
 

A more general slow motion can be achieved using some functions in AVISynth, MVTools. This uses motion compensation techniques to create the frames required.



I have slowed down surfing and snowboarding by a factor of 10 with good results for SD video. I generally convert interlaced to progressive. I have yet to try it on footage from my new HD video camera, but AVISynth should will handle that.

So does AVISynth do that, take each field from an HD frame and convert them into individual SD progressive frames?

You can create 60P in Vegas converting each field to a frame:

1) Download and install Mike Crash Smart Deinterlace filter: http://www.mikecrash.com/modules.php...p=getit&lid=51

(All his filters: http://www.mikecrash.com/modules.php...p=getit&lid=53 )

2) Create a 60P (59.940) project
- Field Order: None (progressive scan)
- Deinterlace method: None

3) Switches
- Smart Resample

4) Apply the Mike Crash Smart Deinterlace filter to the track

5) Render as 60P

Thanks very much :D

Oh just another thought on that - you say 60P, so I'm assuming you're working in NTSC - I'm working with PAL, will there be any conflict in the fact that the resolution will be 540 lines as opposed to 576?

Just create and render a "50.000 (Double Pal)" project (aka 50P) instead. I don't think you'll notice the difference in resolution. By the way, if you know ahead of time that your intended target is slow-motion 50P, you might try to shooting with a shutter speed like 1/100 rather than 1/50.

Ahh nice one, good point. Cheers for reminding me. :)

ignore this

ignore this too