American Cinematographer - July 2007 - 88

The JVC GYHD250U with Fujinon zoom lens above, and below with the H2-CA13U Cine Adapter. wherein the noise crossed the threshold of acceptability was no small feat. Unfortunately, due to extremely limited support for the JVC ProHD (or what should be called HDV Pro) format, I didn’t have the opportunity to take the footage through a full workflow. ProHD can only be played in JVC ProHD decks; Sony and Panasonic do not have decks that support the format. Of the 15 post facilities I consulted in Los Angeles, only one had support for JVC ProHD: Digital Film Tree. Unfortunately, their schedule was so packed that we were not able to book time to review my test footage in their workflow. Ramy Katric, the company’s cofounder and CEO, said Digital Film Tree generally advises clients to “transfer off of HDV as quickly as possible. When they come in with HDV footage, we’ll usually bump that up to HDCam SR right away and take it from there.” The HDV format has always struck me as a rushed concept intended to get “high definition” into the hands of techsavvy consumers. On paper, it is an extreme compromise, trying to force a 1280x720 image or, worse, a 1920x1080 image onto a tiny MiniDV tape. It utilizes the same language as DVDs — MPEG2 compression in GOPs, or Groups of Pictures — to achieve this data squeeze, taking what should be at least 100 megabytes per second (MB/s) and cram- ming it into 25 MB/s (19.7MB/s in the case of JVC ProHD HDV), exactly the same data rate as standard-definition (720x480) MiniDV. The difficulty I had trying to find a post workflow for my HDV footage confirmed my initial trepidation about the format, and some of the results I eventually saw left me more puzzled than satisfied. Before I started testing, I understood that Final Cut Pro HD, an early supporter of the HDV format (even back to version 4), could work with JVC ProHD. Then I discovered that only Final Cut version 5.1.2 could work with the format, but not in 60p. (Avid claims it will offer support for ProHD in the future.) Unfortunately, I only had Final Cut 5.1.14, as did Blissium, a professional editorial house in Santa Monica that I was using at the time. I contacted three other professional editorial facilities that feature Final Cut Pro HD systems, and they, too, only had Final Cut 5.1.14. (While I was doing this test, Final Cut announced version 6 — FCP Studio 2 — but I did not have the opportunity to test this footage with it.) The upgrade from 5.1.14 to 5.1.2 costs $700 (buying 5.1.2 new costs $1,300) and requires an operatingsystem upgrade from OSX to OSX Tiger. Apple, instead, generously provided me with a new Intel Core Duo 2 MacBook for this review, and JVC sent me the BRHD50U ProHD deck. This deck integrated with the MacBook well via FireWire 400 (IEEE 1394), and I had no problems capturing, editing and working with multiple layers of ProHD footage. At the time of my test, I had JVC’s new DTV24L1U 24" LCD HD monitor, and I used it throughout my testing. The BR-HD50U deck has three options for HD output: analog HD component, FireWire 400 and HDMI. The camera has an HD-SDI output, so why doesn’t the deck? On the JVC 24" LCD, I was startled by the level of noise evident in underexposure. I viewed live footage from the camera as well as playback of recorded media from the camera, both via HD-SDI, and playback from the deck via the HD analog component output. Even at 2 stops under, the noise levels were beyond what I would consider acceptable. On playback, any noise I noted in live viewing turned into horribly aliased and blocky artifacts. But later, through the assistance of Birns & Sawyer, I reviewed the test footage using the BR-HD50U deck and a Sony BVM-D20F1U HD CRT and noticed very different results. Even as far as 41⁄2 stops underexposed (the point of loss of detail), the noise levels were quite acceptable, and I didn’t see any overly obtrusive aliasing or blocky artifacts. I cranked the brightness on the Sony monitor nearly to the top and saw little appreciable increase in noise or artifacting. The CRT review returned excellent results and demonstrated a camera latitude of about 71⁄2-8 stops. On the JVC 24" LCD, the results were much more disappointing, 5-51⁄2 stops. Unfortunately, I was not able to compare the CRT and LCD results side by side. The BR-HD50U has a composite SD output for instant down-conversion to SD, and at first I thought this was a welcome feature. But the result was less than satisfactory, with highly compromised black levels, extreme noise and artifacting, and total loss of detail in anything less than 2 stops underexposed; I found the downconversions entirely unusable. On top of this, in addition to the fact that 14 of the 15 professional post companies I contacted do not work with JVC ProHD, the two major duplication facilities in Los Angeles that I typically use for down-conversions also do not work with the format. With the Fujinon lenses, I found a great disparity between the aperture markings on the lens and the aperture readout in the camera’s display, as much as 3⁄4 of a stop at times. I elected to go by the readout in the display as a control for all testing with the ENG lenses, and T-stop markings for the cine lenses. (There is no stop readout in the display when using the Cine Adapter.) The camera offers gain settings from 0 to +18dB, but I found +9dB to be too much noise for my taste. I also would have appreciated the option of -6dB, or even just -3dB, for higher-key situations. To nitpick, the gain switch seemed to be inverted, with high gain in the lower position and low gain in the higher position. I have seen 88 July 2007

American Cinematographer - July 2007

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