Or: HDTV is Alive and Well
By Bob Lamm
Moviemaking has been revolutionized by the advent of high-resolution (High-Definition=HD) digital cameras and recorders. Digital cameras give cinematographers a lot of freedom they didn't have before: The ability to see final-quality work during the shoot, make all sorts of fine tonal and colorimetric adjustments that film doesn't allow, and shoot in low-light conditions that most film cameras can't see. (Some digital cameras are the equivalent of ASA 1000.) This last feature alone is a tremendous aid because it enables much more realistic interior and evening scenes, nothing to say of saving on lights, setup time and heat.
But what really brought digital moviemaking into public consciousness was when George Lucas decided to film his latest Star Wars movie with HD cameras: The original reason was convenience and cost: By shooting directly to a digital medium there was no need for a film-to-digital transfer stage prior to feeding the footage into the special-effects computers. And it didn't hurt that the tape is much cheaper than film and re-useable to boot. But what appears to have very pleasantly surprised the Star Wars team is how good the electronic image quality turned out to be: The producer of the film went on record to state that they were able to safely blow up their HD images by a factor of 100% for special effects as opposed to the 15-17% they had been limited to in film.
Other positive features that the team commented on were the much longer recording time (over 2 hours on some HD tape formats), which saved a lot of distracting film-change interruptions (5 minutes to reload, check for hairs in the gate, etc.) and the fact that the gear worked without a hitch in some pretty hostile environments. (Like the Tunisian desert in the summer.) And the ability to see dailies essentially while they were being shot didn't escape the attention of the director, who arranged to have an on-location editing system to cut that day's footage together so he could see an edit of it by evening.
But the Star Wars team's strongest endorsement of the digital system was the fact that they had a fully-loaded film camera with them during the entire production - required by the insurance company - and never used it. "I think that I can safely say that I will probably never shoot another film on film." were George Lucas' final words on the subject.
It's not just big, special-effects films that benefit from HD cinematography: It's also ideal for independent features. Part of the reason is the much greater flexibility of the cameras: Sensitivity and colorimetry can be dialed in, settings can be so finely adjusted that you can change the color of only a single object in the scene, etc.
But the biggest advantage that HD brings to independent filmmaking - er, moviemaking - is that it's much easier and cheaper to shoot: If you're a wildlife photographer, you can comfortably point the camera at an animal's nest and let it run all day until something happens without worrying about film costs. There's even a special RAM feature on some HD cameras that continuously records about 7 seconds' worth of video into special memory. If something interesting happens, you press the 'record' button and you've automatically got the prior 7 minutes on tape! This is great for filming criminals coming out of courthouses and other stuff where you don't know that you wanted it until after it's happened. HD is also better for medical and scientific photography, were fine, film-level detail is important, but exposure levels through medical instruments can be hard to judge: Being able to see the output while you're shooting avoids a lot of nasty surprises later on.
Post-production on HD is a lot cheaper and easier too: For one thing, there's no need to develop negatives and make prints first! This is a lifesaver for independents since they often need to raise more money after shooting and HD gives them final-quality footage they can show to investors to finance the next stage. And HD editing equipment (and the rental rates it goes for) is rapidly coming down in price: You can now shoot HD and do a basic edit of a feature for less than the cost of shooting film and processing it. You don't have to print a single foot of film until you've sold the feature. (See Sidebar: HD post-production systems are getting very reasonably priced!)
But the biggest surprise for most HD moviemakers is the tremendous amount of stuff that HD post-production systems can do: Compositing applications like After Effects and Digital Fusion are ideal for HD and let you do all sorts of special effects that are literally as good as the film effects that the Hollywood guys use. 3D Animation programs like Maya and 3DS MAX run on these systems too, so you can create entire alien worlds out of mere bits. Not all films need to look like The Terminator, though, but many of them could use a touch-up or two: So it's not uncommon for HD post-production to include small effects like the removal of inappropriate objects in the scene (like Coke cans in a cowboy flick). This used to be very difficult and expensive for even the big Hollywood guys to do - but very quick and easy to do in HD. So much so that several filmed films have been post-produced in HD because of the ease, economy and power...
Finally, the slow but steady advent of HD television broadcasting is making the eventual distribution of high-definition TV programming a certainty. So TV producers are beginning to master their programs in high-resolution formats to insure their long-term marketability and value. This includes well-known programs such as Everybody Loves Raymond, Titus and 100 Centre Street.
HD Formats and Gear
The only wrinkle in the HD ointment is the large number of confusing formats: Here's a quickie guide: (Not all combinations of resolutions/frame/tape formats are available.)
24fps: Exact frame-correspondence with film frames. Captures the 'film look' and is ideal for productions that originate or will eventually be printed to film.
24VFR: True variable-rate frame rate that allows the user to vary shutter speed and exposure between 4 and 60fps. Used for special-effects shots.
23.98fps: Film speed adjusted slightly for seamless conversion to NTSC. Usually done to facilitate NTSC simulcasting and sync with other NTSC equipment.
25fps: Exact frame-correspondence to PAL. Eliminates 4% pitch change that occurs when 24fps film is run at the PAL rate.
29.97fps: NTSC frame rate.
30fps: Compatible with 30fps film and associated audio.
59.94fps: NTSC field rate. Captures fast movement, when interlaced provides the smoothest, most fluid motion reproduction.
60fps: Highest frame rate available in HD.
Film2K: Film quality.
1080i: High-resolution images with efficient data storage.
1080p, sf: Full frame images for high resolution. (This was used at 24fps to shoot Star Wars Episode II onto HDCAM tape.)
720p: Full Frame
Most decks only support a limited combination of resolutions and frame rates. Bit rate gives an approximate idea of the relative recording quality, with higher numbers being better.
HDCAM: Sony format that records 135Mbit/sec on cassettes that look like (but are different from) Digital Betacam. 40 min on small (camcorderable) cassette, 124 min on large studio tapes.
DVCPROHD: (aka D7-HD): Panasonic format that records 100Mbit/sec on DV-type cassettes. (You can use Mini-DV tapes if you need to.) Very compact format and also supports Panasonic's new 24VFR variable-frame-rate recording format. 32 minutes maximum record time on a standard DVCPRO tape.
D5-HD: Panasonic studio deck format that records 235Mbit/sec onto tapes that look like (but are different from VHS) tapes. 124 minutes max on large (bigger than standard VHS) cassette.
D6: Philips/Toshiba format that records 1Gb/sec (1000Mbit/sec) uncompressed HD onto tapes that look a bit like the old ¾" format. 64 minutes on a large cassette.
D9: JVC 100Mb/sec. HD version of Digital S. 62 minutes max on a standard-sized cassette.
Sony and Panasonic are the major players in the HD camera world. These cameras are a bit on the pricey side (about $100,000 depending on model), but you can rent them from places like Rule Associates and Boston Camera for not much more than a film camera. There are a couple of high-end HD finishing houses in Boston and the post-production systems are getting really cheap: For Mac people, there's the Pinnacle Cinewave HD card, on the PC there's a really nice editing/compositing system called HDBOXX from BOXX Technologies in Austin, TX. It lets you do uncompressed HD editing and high-end effects starting at about $50K.
Finally, when your movie is done, you can have a negative and prints made from the digital master. But this may eventually become an obsolete step: Movie theaters are slowly starting to experiment with digital servers and projectors and we may eventually be watching TV - High-Def of course - at the movies!
HD information resources:
Digital Media Net HDTV Buyer: www.hdbuyer.com
HD Equipment Manufacturers
Sony has info about their HD products at www.sonyusacinealta.com.
Panasonic has info about their HD products at www.panasonic.com/hdworld.
Avid makes an HD nonlinear system called DS|HD. www.avid.com.
BOXX Technologies makes an HD editing/compositing system called the HDBOXX: www.hdboxx.com/sm
Pinnacle makes an HD capture/playback card for Final Cut Pro called the Cinewave HD: www.pinnaclesys.com.
Bob Lamm is the Editor of the SMPTE/New England Newsletter and Web site. He can be reached at 617-277-4317, email@example.com.