Advice Needed: Shooting Dance in HD

[Elizabeth Lowrey]

I'm going to be shooting a dance recital this Saturday. In the distant past on these jobs, I was always shooting SD 60i. The last recital I shot, two years ago, I shot 30P HD, both firsts for a full job. I'd shot rehearsal footage at SD 30P that I thought looked good, but I was a bit disappointed with the amount of motion blur in some of the actual performance footage.

With the cameras involved in the upcoming shoot, I have the option to shoot 1080 at 60i or 720 at 60P. Final DVD will be mastered to two formats, one HD BluRay and one SD. The SD will obviously be 60i, requiring an interlace if I shoot 720P. I've done only a couple of interlacing tests (in Sony Vegas, my editor of choice) on some old 720 60P Varicam footage I had lying around. It seemed fine, but I'm wondering if anyone has experience interlacing a wide range of 60P footage for SD, what tools and workflow you used, and how pleasing your results have been, particularly in relation to fast motion and the rendering of motion blur. I'm renting the cameras and will have one in hand to shoot some rehearsal footage tests on Friday, but I'd like a head start on my decision-making as far as what format to use for the actual performance. Any help much appreciated.

 

[Björn Benckert]

Are you shooting on a red cam?
If so I would advice you to shoot 23.978p and then convert it to whatever standards. That works well/the best as long as your conversion is done correctly.

 

[Elizabeth Lowrey]

No, not shooting on RED for this but on Sony HD cameras, including 2 EX-1s. I can't think of a scenario offhand in which I would choose 24 fps to shoot dance, except as part of a film where that was the project rate. The frame rate is just too slow, IMO, for the kind of clarity that I think most dance schools and patrons are looking for and which I myself prefer.

 

[Craig Parkes]

Elizabeth, my personal recommendation would be to shoot 720p60.

You won't need to deinterlaced this footage for SD delivering, what you will need to do is render it out as interlaced footage.

The exact workflow for doing this depends on your software. One problem you can run into is if you use a lot of default settings with conversion software it will simply throw away every other frame so you don't actually get proper 60i footage from your 60p master, instead it first throws away every other frame (turning your 60p into 30p) then splits these into fields, and renders out a 60i film where there is no temporal difference between the upper and lower field.

I honestly have no idea how Sony Vegas handles this, and have only worked around this issue in Final Cut and After Effects - but you really do have to look out for how you do this otherwise the advantage of shooting 60p will be lost on your SD version.

It's actually the key reason I prefer 720p as an originating broadcast format when going to both to HD, SD and Web. You have a native high frame rate master, that can be split into proper interlaced fields on upconversion and downconversion without having to deinterlace at any point.

From browsing some forums it looks like Vegas may handle the interlacing properly if you just drop a 60p clip on a 60i timeline. If so then you are pretty much good to go.

 

[Elizabeth Lowrey]

Craig, thanks so much for your input. (BTW, I don't know why I was so spaced out when I wrote the original post, but everywhere I said "deinterlace" I actually meant "interlace". I edited the post to correct it.)

I'm googling this issue for treatment in Vegas right now, which I should have thought to do first. But this forum is so responsive and filled with such knowledgeable people that it spoils me into just asking questions instead of doing grunt work research.

 

[Gavin Greenwalt]

In my experience, dance performances are so dark that you need to shoot like 1600+ ISO. Is 30p 1080 not an option? The motion blur might be frustrating... but the alternative is ridiculous noise.

 

[jimhare]

And can't you just control motion blur with shutter speed instead of frame rate?

Unless you are specifically going for an interlaced video look, you may be better to shoot a lower frame rate with a faster shutter.

For example, what playback scenario will you have to play the footage at 60FPS outside of the studio?

 

[Craig Parkes]

And can't you just control motion blur with shutter speed instead of frame rate?

Unless you are specifically going for an interlaced video look, you may be better to shoot a lower frame rate with a faster shutter.

For example, what playback scenario will you have to play the footage at 60FPS outside of the studio?

Every SD set will play the footage back at 60fps, just interlaced.

It's important to remember that despite the pain in the ass that is interlaced, for some programming, including those with high levels of motion where you are looking to SEE the detail of that motion, improved temporal resolution is better than improved spatial resolution.

If the stage is too dark to film at 60fps then you would have had a problem in SD days as well when it had to be shot at 60i, shoot at 30p and crank up the shutter and put back out to 60i for DVD etc it'll look strobey and still be darker due to the increased shutter speed if lighting is a problem anyway.

Interlacing is a horrible hack that we unfortunately still have to live with, but 60p or 50p delivery ACTUALLY DOES have advantages, even if it's less 'cinematic' (until the Hobbit comes out I wager) and you can watch 720p60 on any Blu Ray player/HD combo and DVD's are pretty much always 60i if they aren't specifically progressive films with pull down and the progressive tag (and even then still encoded at 60i technically, just played back progressively on players that can handle that.)