HD Slow Mo with Phantom

Cinematographer Jim Matlosz reports that ongoing developments with the Vision Research camera are offering an attractive alternative to commercial and narrative TV clients looking for high-speed photography on a budget. Still, he warns, in order to maximize the image quality the camera has to offer, users need to be thoroughly prepared on the postproduction end to make the most of the raw image data that comes from the camera's sensor.

Previous iterations of the company's digital high-speed camera equipment have been embraced for some time. The Phantom HD High Speed was introduced in the fall of 2006. The Phantom HD High Speed—capable of 1920x1080 HD or 2048x1535 2K resolutions and featuring a PL lens mount—started to be routinely used by many artists for the types of sequences that previously would have been done only with a high-speed film camera.

Matlosz became a specialist in high-speed photography 10 years ago as a technician for Photo-Sonics high-speed film cameras, which he continues to recommend for many high-speed jobs he's offered. But when budgets don''t allow for film stock—Matlosz sees hourly rates in HD telecine bays as the most costly roadblock to shooting film for high-speed sequences these days—he is eager to work with the Phantom, which can yield a 14-bit, 1920x1080 image at any frame rate between two and 1000fps. (It should be noted that Vision Research, Photo-Sonics, and other companies currently make high-speed digital cameras that can record even faster, but at lower resolutions.)

Although he likely wouldn't use the camera for an all-sync sound job (timecode remains an issue in such situations), he did recently mix Phantom footage with 24p sync sound footage—slating it with the traditional Smart Slate used on film shoots—for certain shots in otherwise slow-motion spots featuring basketball star Kobe Bryant. By doing so, he points out, he eliminated the need to carry separate cameras for sync sound and high-speed photography. The spots for Bryant's new sneaker product, the Nike Zoome Kobe III, were produced by the athlete himself and the agency, Zambezi, are offered on the site www.kb24.com. You can see Matlosz favorite shot at www.kb24.com/media/video/144.

Matlosz also used the Phantom HD for some CBS bumpers and tags for CSI: Crime Scene Investigation in which slow-motion shots of fingernails and bullet casings fall through the air. He's also done some bumpers and tags for the Food Network showing ultra-slow motion symbols of cooking—ice falling into a glass, water, smoke, fire, and such.

The Phantom HD uses a single-chip Bayer pattern CMOS sensor that sends its 14-bit image data in a proprietary raw format directly to an attachable flash memory CineMag drive that the company manufactures in 512GB and 256GB versions. In the 1920x1080 format, the 512GB CineMag can hold approximately 90 minutes worth of material at 24fps.

Part of the efficiency of the system comes from a minimal amount of data processing both within the guts of the camera and in the drive.

"The drive uses a form of lossless compression," Matlosz says. "It compresses the whole file rather than individual frames, something like a zip file. The drive itself isn't formatted, and so it doesn't fragment like a PC drive would where data is scattered all over the place. It's efficient but the drawback is you can't delete individual files."

As the drive fills up, Matlosz will use his PC and LaCie or G-RAID hard drives to do a direct file transfer to free up the flash drive for more shooting.

"I'm hoping for Ethernet drives at some point," the cinematographer says. "Right now, I'm using E-SATA and FireWire 800 to transfer the information."

The aspect of working with the Phantom, he says, that has frightened some and caused others to come up with disappointing results has to do with what happens next: the postproduction workflow. Like a number of digital cameras that spit out some form of raw file that requires further processing down the line, Phantom HD sends out files in a raw format that must be de-bayered in post and then translated into files that retain all the information the camera is capable of.

"The Phantom HD," Matlosz says, "does have an HDSDI-out port that sends a quickly downconverted 4:2:2 HD signal to any kind of tape deck or DDR with HDSDI-in. People have used that instead of the raw format for their final images, but I would only use it for a monitor and playback on set. If you're shooting 35mm film, would you convert it to 16mm just because you could?"

There are several approaches for converting the raw files to something more standard such as a DPX or TIFF. Vision Research has its method, as do Glue Tools, Iridas, and Abel Cine Tech, among others. Matlosz is tight-lipped about the particular method he's worked out with the post houses he frequents. He likes to keep that as part of the service he offers, but the workflow with all of them involves de-bayering each frame and converting it to a16-bit TIFF file. The raw file is 14-bits. "So it doesn't make sense to then go to an 8-bit TIFF or DPX and lose that information,” Matlosz says. “Once you have your TIFF sequence, you can go from there into whatever tool you need to use—Flame, Inferno, Final Cut, Avid."

Matlosz says that the fact that a labor-intensive post process is involved has an odd effect on people who not long ago would have thought nothing about the even more time- and money-consuming telecine process. For this reason, some either try to bypass the raw workflow by recording the lower-quality HDSDI to tape or avoiding the Phantom altogether. But to him, the fear makes little sense.

"I tell people, 'It's no different than what we'd do in film,' " he says. "They might be so spoiled by video and tape that when they have to go an extra step to get a quality image, it seems too difficult. We shoot film, process it, and then a day or more later, we transfer it and then cut it. That's something we're willing to do because of the quality we get. This workflow has to be done right, but it's still not as expensive as telecine.

"I think that as more people see the quality of high-speed cinematography, they can get with the Phantom and the right workflow, they'll start to realize it's worth it.”