As many camcorder manufacturers have discovered, three low-resolution sensors can sometimes take you a lot further than a single high-resolution sensor. But while this may be the case for a standard-definition world, it doesn't mean the same is true for hi-def.
JVC's Everio GZ-HD7 is a 3CCD hard-drive-based HD camcorder that attempts to follow this theory. It offers a good range of manual features, but can its high-definition image quality justify its four-figure price tag?
With a few exceptions, the control layout seems designed for actual manual use rather than for show. We docked it a point in the design ratings, though, because several important shooting controls -- gain control, wind filter, white balance -- are buried in the menu system, and because you're forced to use the LCD too often. The latter is especially significant in light of the HD7's poor battery life.
Perhaps it's because JVC uses three extremely small 1/5-inch sensors, each with approximately 976x548 pixels, interpolating and interlacing to generate 1,920x1,080-pixel 1080i HD video. Perhaps it's because of the demanding MPEG-2-TS (transport stream) compression and encoding the HD7 uses to write video to its 60GB hard disk drive.
But whatever the reason, the HD7 simply can't produce video to rival that of similarly priced single-chip competitors like the Sony Handycam HDR-SR1. It's a pity, too, because the HD7 has all the features you'd expect from a camcorder in its price class, including manual aperture and shutter speed adjustment; a very nice manual focus implementation; low-noise, low-light video; bright LCD and eye-level viewfinder; an external mic input; and an accessory shoe.
The HD7 can output in two different 1080i formats. The first, 1,920x1,080 pixels, dubbed 'FHD' for 'Full HD', uses variable bit rate compression for a theoretically better picture. The second, 1,440x1,080 pixels, dubbed '1440 CBR' uses constant bit rate compression, and is the HD format you must use if you wish to edit your video with iMovie -- iMovie doesn't speak FHD.
On Windows, we suggest you stick with the bundled Cyberlink software for playing, editing and burning your FHD video. Figuring out which third-party software will work with FHD and how to finesse it takes some major Googling.
Performance represents the weakest aspect of the HD7. First, the battery lasted for only 20 to 30 minutes of our field testing, despite the fact that we shoot primarily via the less power-hungry eye-level viewfinder.
Second, the optical image stabiliser seemed completely ineffectual, however the product manager did admit that the OIS is "underperforming" and that the company is "looking into it".
The lens focuses relatively fast and displays surprisingly little chromatic aberration -- just the expected amount on high-contrast edges -- but exhibits some barrel distortion at the wide end, which isn't so wide that it's worth forgiving. Only the audio performed as expected, and the wind filter completely cut the effect of the day's loud breeze.
The video generally looks pretty good, but you can get much better HD video from tape-based models such as the Canon HV10 or HV20 for far less money. You may be willing to pay a premium for hard-disk-drive convenience, but you shouldn't sacrifice video quality.
Some of the problems with the HD7's video include severe interlace artefacts, horizontal jitter and stutter and blown-out highlights. Video looks far sharper when shot using a tripod, with very little motion in the scene, but even then you can see interlace artefacts while zooming and on moving objects. For better or worse, the FHD and 1440 CBR video looked quite similar to each other.
All of this adds up to a pretty disappointing camcorder, especially given the JVC Everio GZ-HD7's relatively high price tag. Check out any of the HD models in our Camcorder Reviews section for a better option.
Additional editing by Kate Macefield