HD For Indies

UPDATED WITH HDV INFO ON 9/8/04:

I've been looking into some stuff, so I decided to review what the various formats can do.

HDV

Not really a professional format, but I'm sure some indies will use it.

HDV resolution 1:

Playback frame size: 1280x720
Acquisition frame size: 1280x720 to tape
frame rate/s: 30 fps progressive

no interlaced 720 signal, no 24p

bit depth & color space: 8 bit, 4:2:0 (alternates which color channel gets recorded)
datarate: 19MBit/sec (about 2.375 MB/sec)
compression type: MPEG-2 transport stream, with GOP (group of pictures) 15 (think of it as keyframes every 15 frames)

HDV resolution 2

playback frame size: 1920x1080
acquisition frame size: 1440x1080 to tape (but the Sony upsamples 960x1080 to this)
frame rate: 60i (interlaced, no progressive options)
bit depth and color space: 8 bit, 4:2:0
datarate: 25Mbits (about 3.125 MB/sec, slightly less than DV)
compression type: MPEG-2 transport stream, with GOP (group of pictures) 15 (think of it as keyframes every 15 frames)

DVCPRO HD:

1280x720 10 bit 4:2:2 at 59.94 or 60 progressive fps. 24, 25, 30 fps also possible as standard stuff, or anything from 4 to 60fps if the hardware or software frame rate converter is used.

1920x1080 10 bit 4:2:2 at 59.94 interlaced

Reality:

10 bit 1280x720 4:2:2 progressive off the HD-SDI tap gets sampled down to 8 bit 960x720 at 4:2:2 colorspace then compressed to about 5 1/2 MB/sec
10 bit 1920x1080 interlaced only off the HD-SDI tap (gets sampled down to 8 bit 1280x1080 at 4:2:2 colorspace then compressed to about 14 MB/sec

HDCAM

1920x1080 10 bit 4:2:2, progressive or interlaced, 24p possible (psf)

1920x1080 10 bit 4:2:2 off the HD-SDI gets sampled down to 1440x1080 8 bit at 3:1:1 colorspace then compressed to something like 22.5 MB/sec (don't have hard #s)

HDCAM SR

1920x1080 10 bit 4:4:4, progressive or interlaced, 24p possible (psf)

Reality:

Hey, this one (finally) works well:

1920x1080 10 bit RGB 4:4:4 of the dual HD-SDI taps actually stays just that - 10 bit 1920x1080 RGB 4:4:4. It is then compressed with MPEG-4 SP (Studio Profile) with 4.27:1 compression, results in a 50 MB/sec datastream to tape. Uncompressed off the taps, that signal is about 180MB/sec for 24fps.

Panasonic D-5:

1920x1080 10 bit 4:2:2 progressive or interlaced to tape as I understand it. 1080p24 possible. The deck is $99,000. HDCAM SR seems like better quality, better deal.

Synopis:

I see two major categories/price points at this point in time (as I understand it so far, blah blah blah, disclaimer disclaimer). You can split hairs and make other choices, but in terms of final quality,

Budget level 1:

Go for the the Varicam. It can shoot variable frame rates, and while Sony originally touted the increased resolution of their system, they, ahem, don't focus on the fact that it subsamples the colorspace at 3:1:1. While the Sony starts with more pixels, it throws out lots of information before it compresses it. The Panasonic, as the numbers and user reports bear out, starts with fewer pixels but keeps more of the color data. Shooters like it's good color reproduction, and it's ability to do heavy color correction without having the image break up heavily. Panasonic's CineGamma capabilities have also been highly lauded.

But the post process is soooooo lovely to work with in Final Cut Pro HD when using the AJ-JD1200A deck. Source camera quality 8 bit 4:2:2 720p24 is only 5.7MB/sec with 2 channel audio, and FCP HD can do realtime color correction, FX, etc. with it.


Budget level 2:

If you can reach the next big threshold, go for a full size, full bandwidth solution. Shoot with Sony F950 to HDCAM SR in 4:4:4 RGB mode via dual link HD-SDI. For the money, this is a very nice solution. Full res RGB color with no color subsampling, and very very light compression. Described as "visually lossless". I'd like to see some heavy/extreme color correction tests to compare HDCAM SR to straight-to-disk solutions.

The data rate is quite a bit higher for this - if you're going to try to hang on to all that quality, you've got to go uncompressed 4:4:4 10 bit, and that's something like 180 MB/sec. Yowza. That's about 640GB/hr for online work. To quote Roy Scheider in Jaws:

"We're gonna need a bigger boat."

Beyond that:

The Thomson Viper Filmstream recording to HDCAM SR is a high quality but logistically complex solution. 10 bit log (not linear, as all else mentioned here is) 4:4:4 RGB. This is what was used on a lot of night footage in Collateral. They decided not to record straight to disk as impractical at this point in time. Unless you're shooting greenscreen, I wouldn't see a strong/practical reason to do so.

In post, you'd need even more space, since the source footage isn't really watchable/editable. I need to do some thinking on how this workflow would really shake out. The possibility of having an HDLink or One2One do a hardware based log==>lin conversion for monitoring makes the workflow easier, but it's still quite complicated. Not for the faint of heart.

Beyond that to the point of not yet: the Dalsa Origin shows a lot of promise, but it isn't a very realistic shooting possibility as yet. Shoots a 4K image, but it's a humongous datastream - takes a quad 2 gigabit fibre link just to carry the datastream.

But because it shoots log, it complicates shooting, posting, and color correcting SUBSTANTIALLY. From what I can gather this is the best image quality you can get with a camera that has a reasonably viable production methodology. The Dalsa (mentioned below) has to be tethered to a huge disk array at all times...not terribly convenient.

The Kinetta camera doesn't exist yet, and based on what I've seen, their hope for small drive modules is going to take a while to achieve. But I haven't read up on it since NAB.

UPDATE SUNDAY NIGHT: I forgot to mention - don't judge the quality on the data rate alone. Not all compression schemes are equal. For instance, the MPEG-4 Studio Profile used in HDCAM SR is supposedly better than the DCT based compression used in HDCAM (or so I read...somewhere...NOT gospel). So don't go comparing data rates in one format as if they were on the same "scale" as data rates in another format.

Links I found/used while working on this post:

http://www.creativecow.net/forum/read_post.php?postid=109108642875955&forumid=126

http://millimeter.com/mag/video_nab_12/

http://www.williamsdp.com/24p_difference.html (this one's pretty good)

http://www.digitaltelevision.com/publish/dtvbook/ch3.shtml (good one also)

http://www.hd24.com/compression_numbers.htm

http://videoexpert.home.att.net/artic3/262hdvr.htm

http://www.uemforums.com/2pop/ubbthreads/showflat.php?Cat=&Number=22149&Main=22036

http://catalog2.panasonic.com/webapp/wcs/stores/servlet/ModelDetail?storeId=11201&catalogId=13051&itemId=68620&catGroupId=14594&displayTab=O&surfModel=AJ-HD3700B&surfCategory=D-5%20HD%20Mastering%20Systems

http://www.vtpcorp.com/htm/panhdvtr.htm

http://www.thomsongrassvalley.com/products/cameras/viper/ (this is the Viper home page, lots of good stuff to learn, download the PDF FAQ, it's a good overview)

-mike