JVC Professional presenta GY-HD250

Ergonomic design sets the GY-HD250 apart from its competitors in the $5,000 to $14,000 range. Ten-pound camcorder (with a viewfinder, lens, microphone, battery, and tape) rests comfortably on your shoulder. Genlock accepts tri-level sync or black burst with controls to adjust phase (horizontal or subcarrier). Internal timecode generator locks to external sources. Uses interchangeable lenses designed for 1/3-inch CCDs. Optional studio kit (multicore adapter, camera control unit, and studio viewfinder) available. Can record 720p HDV at 60 fps.

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Editing 720p60 HDV not currently supported by Apple or Avid. If you record in this format you'll need to uncompress and capture via HD-SDI output. The built-in neutral density filters labeled 1 (ND 0.6) and 2 (ND 0.12) do not offer enough light reduction to shoot day exteriors at stops below f/5.6. No -dB gain setting. White shading not automatic; the camera doesn't have standard manual controls, instead using a third approach--RGB controls. Paint controls, offering a limited range of adjustment, earn a Òjust adequateÓ rating (with the exception of the saturation control). Operator's manual confusing. The 1080i output cannot be recorded in camera. Focus assist feature of minimal help.

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A shooters' camera designed for indie, doc, and reality TV shooting that can be converted into an inexpensive studio camera. If recording 720p HDV on tape meets your needs, this camcorder is an excellent choice. Editing long GOP MPEG-2 (HDV) at 720/60 may be supported by Apple and Avid in the future but stick to shooting 720/24 or 720/30 until support is assured.

JVC's GY-HD250 uses three 1/3-inch 1.1 million-pixel IT CCDs to record 720p in the HDV format. The camera has native 16:9 (1280 x 720) progressive CCDs and records 720p at 24, 25, 30, 50, and 60 fps. JVC advertises that the HD250 outputs 1080i signals, cross-converting the 720p output; however, this output is only available as an HD-SDI signal. In this mode, you must record the signal on an external recorder.

The standard package ($10,995) includes a Fujinon 16x lens, microphone, SD memory card, tripod plate, and Anton-Bauer Gold battery mount. Other configurations are available. The standard version of the camera measures 19.7 inches (500 mm) x 8.8 inches (224 mm) x 9.5 inches (243 mm) high and weighs 8.3 pounds with lens and microphone. Lenses attach via JVC's 1/3-inch bayonet mount. Optional adapters are available from JVC to mount 1/2-inch lenses ($799), 2/3-inch B4-mount lenses ($799), and even prime film lenses (with JVC's new HZ-CA13U PL, $4,395).

I tested the GY-HD250CHUAB ($11,085) package. This package adds an Anton-Bauer Tandem 70 charger/power supply and a Dionic90 battery, but doesn't include a lens. For my tests, JVC supplied the Fujinon HTS18X4.2BRM 18x zoom lens ($10,800), which pushes the cost to $21,885 and places the HD250 package at the low end of the mid-range camera options.

The I/O section of the camera includes genlock, 1394, Y, Pb, Pr, and HD-SDI connectors.

The GY-HD250UAB package ($12,085) adds the standard Fujinon 16x lens. This package would place the GY-HD250 at the high end of the low-cost camera options. DV also received JVC's HDFilter set ($799) that consists of six Tiffen 82 mm screw-in filters (ND 0.6, 85, 80A, Circular Polarizer, HDTV/FX2, and Clear) and a storage pouch.

Fujinon's 18x zoom lens has a focal range of 4.2 to 76 mm, which equates to about 30 mm to 545 mm on a 35 mm still camera. The lens has a maximum f-stop of 1.4 that doesn't change as the focal length increases, which is a big plus. Lens breathing is better on the 18x than on the standard 16x lens. Even so, it's still a noticeable problem when rack focusing on stationary objects. All the standard servo-zoom features-iris controls, speed control, manual or servo switch, remote control connector, back focus adjustment, return and record switches, and macro focusing ring-are included. In addition, a quick zoom button lets you snap in to the 76 mm focal length to check focus, returning to your starting focal length on release.

Recording

Three menu settings determine how the camera captures and records: Frame Rate, which can be set to 60/30, 50/25, or 24; REC, which has different options depending on the Frame Rate setting; and 1080i Camera mode, which can be turned on or off. The camera automatically resets itself by powering down and then turning itself back on when you execute a change in Frame Rate. Selecting the 60/30 fps rate lets you record HDV at 720p60 or 720p30 and DV at 60i in NTSC on the camera distributed in North America (HD250U). The 50/25 frame rate lets you record HDV at 720p50 or 720p25 and DV at 50i or 25p PAL in the European version of the camera (HD250E).

The 24 fps rate lets you record HDV at 720p24-and in the HD250U version, DV at 24p-with either a 2:3 (standard) or 2:3:3:2 (advanced) pulldown. The Frame Rate setting also determines what will be output when the 1080i Camera mode setting is on. When Frame Rate is set to 60/30, the camera outputs a 1080i60 signal (in the 50/25 setting, it's a 1080i50 signal) via the HD-SDI and component outputs, and feeds an NTSC or PAL signal to the composite video output.

Thankfully, you can display the recording setting in the viewfinder to make sure you have the camera set correctly. But I was thrown for a loop when I set the camera to 1080i60, pressed the record trigger, and saw an error message in the viewfinder. I had to dig through the manual to discover the camcorder can't record 1080i HDV. The purpose, it appears, is to offer the 1080i HDV option for studio/live feeds only. It's disappointing given that the data rate for 1080i HDV is identical to DV, which the HD250 has no trouble recording.

Timecode can be set from the camera menus or LCD screen. Setting timecode on the LCD screen is a two-finger or two-hand operation. You press and hold the status button while pressing a user button. The shutter dial is used to change the numbers. You need to do it once or twice to realize that you can reset and set timecode quickly using this method. There are two switches under the LCD screen to select user bits/timecode display and rec/free run timecode.

Image controls

The HD250 has an adequate set of image controls for a camera with a 24-bit digital signal processor. The video gain range is from 0 dB to 18 dB and the value can be assigned to a low, mid, high switch. In my tests, the camera's ISO rating was about 500. Consequently, it would be very helpful if the video gain range began at -6 dB for exterior day shoots.

A black stretch/black compress control offers five steps in either direction and is enough to handle most situations. The preset white balance can be switched from 3200K to 5600K, so there's no need for a color-correction filter wheel. There are red and blue offsets for white balance so you can make subtle adjustments. The white clip and knee settings are very limited. White clip can be set to 100 percent or 108 percent. The knee point setting goes from 80 percent to 100 percent in 5-percent steps. There is no slope adjustment. In practical terms, you're probably better off using the gamma setting choices, which you can switch from a Standard video gamma to Cinema to Filmout. The Cinema setting is designed to mimic the extended dynamic range of film on a monitor. Filmout is intended for outputting to film. I did not test how each of these gammas performs when output to film. It's curious that the Cinema setting-which adjusts the gamma and matrix settings to Òthe characteristics of a movie screen,Ó according to JVC's manual-isn't intended for output to film.

The gamma correction curve can be adjusted in 11 steps from ±5 and normal (0). Given the limits of the HDV data rates, adjustments made to gamma tend to rob Peter to pay Paul. If you want more gradations in the blacks, you end up with fewer gradations in the highlights or vice versa. The color matrix choices are Off, Standard, or Cinema. You can adjust the matrix settings in the Standard or Cinema positions. The controls are labeled Red, Blue, and Green gain and Red, Blue, and Green rotation. Gains increase or decrease saturation. Rotations adjust the phase along the Red/Cyan, Green/Magenta, or Blue/Yellow axis. In my tests, the range of adjustment was extremely limited for the rotations, although the gains were less limited.

The shutter controls are excellent. You can display the shutter as fractions or degrees, whichever is more comfortable for you. The shutter range in steps goes from 1/6 to 1/10,000 of a second or from 360 to 11.2 degrees. The variable shutter control can be adjusted from 0 degrees to 360 degrees or from 1/frame rate + .01 (e.g. 1/24.01) to 1/10489.5 of a second. You can also use a slow shutter feature in low light situations or for creative purposes.

The white shading control is odd and a potential disaster. Rather than adjusting H and V saws and parabolas for the Red, Green, and Blue channels, there are three controls for R, G, and B level. The manual suggests looking at a monitor to adjust white shading. This is a very bad idea. There are also no warnings to do this procedure while aiming the camera at a perfectly flat nontextured white surface. White shading should be done using a waveform and vectorscope by a trained professional. I can only conclude that the range of adjustment here is minimal or that JVC expects most people to ignore this menu setting and leave it as preset. JVC says it's creating an updated user manual that will include a clearer and more detailed explanation of how to perform the white shading adjustment.

Ergonomics

Camera operators who've used ENG/EFP cameras will feel very much at home. The HD250 is a scaled-down ENG camera that almost feels too light on your shoulder-it weighs only 10 pounds with an Anton-Bauer Dionic battery. Operators shooting documentaries, event coverage, and reality television will really appreciate the HD250's ergonomics and minimal weight. Most prosumer camcorders are rectangular bricks that require a brace to place on your shoulder or leave you with the option of holding all the weight with your arms. The HD250 is a camcorder you can use comfortably all day.

The headphone earpiece for monitoring audio is a nice touch. Most of the buttons and switches are in familiar places-another plus. The focus assist feature is of minimal help whether you select blue, red, or green. It works best when you're zoomed in.

A Camera/VTR switch must be set to VTR to operate the tape controls. You can't display a center mark unless you also choose to display a safety zone in the viewfinder. The zebra setting is limited to a choice of a band from 60 to 70 percent, 70 to 80 percent, 85 to 95 percent, or to over 95 percent or over 100 percent. If you're upgrading from less expensive cameras, this will be a positive, but if you're moving down from more expensive ENG/EFP cameras you'll be annoyed at the limited choices.

Workflow and compatibility

The HD250 follows long-established workflows for tape-based systems. The advantage of a camera that outputs 720p60 is limited to live television or when an external recorder other than an HDV recorder is used. Because it offers the highest frame rate, 720p60 is the most desirable ATSC standard for 720p-but to edit 720p60 footage, you'll need to uncompress and capture via HD-SDI output. JVC's 720p24 and 720p30 HDV are supported by NLE manufacturers, and it's likely that the new 720p60 HDV format will be too. In the meantime, you'll need to consider the consequences of shooting in a format you can't edit.

This image shot just before dusk, on a very cold sunny day, has good saturation and pleasing color reproduction. Note the reflections in the windows of the clouds and setting sun. There are minor chromatic aberrations on the street lamp on the far right. Exposure is critical. The deep shadows in this image were crushed to preserve the highlights. There is practically no shadow detail to recover in post.
©2007 R. M. Goodman

Performance

The HD250 produces high-quality images, though recording in the HDV format means capturing the output of the camera as 8-bit images with 4:2:0 color sampling. I rated the camera at an ISO of 500. To shoot in sunlight with an f-stop under f/5.6 meant setting the camera's built-in neutral density filter to ND2 (an ND 0.12 filter) and adding a circular polarizer plus an ND 0.6 filter on the camera. With two screw-in filters, there was vignetting at the widest focal lengths. A better solution is to use a matte box with 4 x 4 filters.

The camera draws 24 watts of power; in my tests, an Anton-Bauer Dionic90 lasted 3 hours.

Conclusions

The ergonomics and interchangeable lenses are strong points of the GY-HD250. The recording format-HDV-is the limiter. If the HDV format meets your needs, this camera is a winner. If you need a high-quality inexpensive camera for studio use or live display via 720p or 1080i HD-SDI, this camera is a winner. The 1080i HD-SDI signal looked very sharp to my eye when displayed on a 1920 x 1080 flat panel monitor fed by a Blackmagic Design HDLink box. I wasn't able to record the 1080i signal to evaluate it more thoroughly, which you should do before you use this camera as a 1080i source. If you need higher data rate recordings, you'll have to hope that some manufacturer makes a camera that records more data and gets the ergonomics and weight right too.

 

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