True slow Motion on a digital camera

[twistedperspective]

Hi,
I'm interested in filming portions of a short film in SLOW MOTION for my degree course in Film and Video.
I understand that (in the medium of Film)Frame rates can be set to say 48 frames per second and with special equipment as high as 300 fps.

Is there any such equipment that can be rented or bought to a small budget that uses digital technology instead? I do not want to simply space the 24 frames out like is often suggested.

Help appreciated

[DAVE M]

I spent ages trying to find a source that would hire them - no luck.
Often they are "digital" in that the signal is recorded to a hard drive before replay at slo mo.

You'll find that most are monochrome as it's cheaper and better for scientific work. colour will add to the cost.

Most nature stuff is still done on high speed cine.

try people like the transport research lab at crothorne, insurance place at thatcham (both in berks) as they may use high speed. also try any uni that does a lot of engineering stuff.

Bear in mind that more frames = much more light.

if I see an advert in the trade papers I'll let you know.

[Benfrain]

There is a HD camera from Panasonic which will record true slow motion but it costs around £600 a day to hire. At the moment this is the only system that will do it. The camera is called the AJ-HDC27V and you can find out more about it at www.panasonic.com/hdcinema

[Alan Roberts at work]

The Panasonic camera has now been renamed AJ-HDC27 (i.e. they've dropped the V). The non-slo-mo version of the camera appears to have been dropped. The problem with using this camera is that you need access to some specialist Panasonic conversion kit to get the pictures out.

[benhaines]

Hya....

As a software dude I would say do it in post

Seriously though... camera is going to have to do anything fancy in realtime... so I doubt the hardware solution is anywhere near as good as a software solution.

ReVision FX have a product called Twixtor and RealViz have a product called ReTimer that both do an amazing job.

The app allows you to slow or speed up time with a spline, once you have done that it will go off and analyse your footage and detect the motion vectors... once it has done that it calculates the frames in between for you

The effects have been used in films such as the Matrix, X-Men, etc...

They aren't cheap but they are the best...

Unfortunately the company that made the software used on the matrix have stopped work on it but the two mentioned above are available.

Good luck Ben

[Alan Roberts at work]

Speeding up in post is fine, but not slowinf down.

Speeding up involves throwing away information. Ideally it should use a temporal filter to increase the integration time so that the pictures don't look too sharp, but you can get away with not doing that.

Slowing down in software is a lot harder. You're trying to invent information that you don't have. In an ideal world, you could use software to anayse the picture and identify which parts are moving at what speed and in which direction, and draw the new "in-between" images based on that. Snell & Wilcox had a beats that did that a few years ago, it would slow down by up to about 64:1. But it was hugely expensive and no-one bought it.

Ben Frain's advice is correct, the best way to get a slow-down is to shoot fast. The Pansonic AJ-HDC27 will go to 60p, so you can get about 2.5:1 slow down without having to resort to special tricks. If you want any more than that, then you should be thinking of high-speed film cameras.

Unless you want to do it all on the cheap, in that case shoot normally and slow it down on the time-line. If that looks ok to you, then you've done the job, but it won't work well for all images. That's where the real money goes.

[benhaines]

Hya

Alan, I guess I would agree with you, but have you seen the quality of the slowed down footage... since S&W stopped work on FloMo the technology has come on a bit... also Twixtor is mear smidge of what S&W were selling theirs for.

Just thought that considering this is a degree project, funds are going to be limited and therefore an HD camera is just plain silly talk.

BTW S&W had a bloody machine that did the flomo stuff in realtime (my dad is in charge of post production there

Regards Ben

edit: oh and as its his/her first time with it I thought post would be safer

[This message has been edited by benhaines (edited 23 April 2002).]

[Alan Roberts at work]

Yes, I know the S&W kit was real time, I have some inside information on that

I'm not laying down any rules here, just making sure that all ways of doing it are made known, with the limitations spelled out. Software slomo does indeed work, but it's a process of inventing information based on a best guess using the available information. It's always going to be hard, and will always fall down if given unsuitable material. That's why the S&W box never made it to market.

The best way will always be to shoot it fast and replay slow. Spend the money to get good images, and the rest is easy.

[Chris B]

hi,

I remember seeing a consumer DV camera that did slo-mo a while (1-2 years) back in CV. I think it was a panasonic -the catch was that it only did it at half the screen size of normal DV - depending on the graphic design of your project this might be acceptable...

Chris

[chris thomas]

Shoot fast is the correct way, but if you've already filmed something, I found this company which has a software solution which quite impressed me. Download the 7mb car spinning demo.

http://www.dynapel.com/private/mp_video.htm