1080/60i @ 24 Mbps; 1,440x1,080/60i @ 12, 7, 5 Mbps
(all video interpolated up from 1,664 x 936)
1080/60i @ 24, 17, 12, 5 Mbps
(all video interpolated up from less than 1440x1080; actual dimensions n/a)
1080/60i @ 17, 13, 9; 1,440x1,080/60i @ 5 Mbps
1080/60i @ 24, 17Mbps; 1,440x1,080/60i @ 9,5 Mbps
mic, headphone jacks
The feature set is pretty typical. Most notably, there's face-priority AE/AF, video categorizing, interesting time-lapse video, and a faux motion-sensor mode that records when it detects changes in brightness.
Unfortunately, none of these makes up for the lack of optical image stabilization. JVC fails to distinguish between optical and electronic stabilization (EIS) on its Web site, referring to both as the "Advanced Image Stabilizer," but the HM300/320 manual refers to it as the "digital image stabilizer." Unfortunately, EIS can degrade video quality, and the camcorder simply doesn't have the extra pixels to spare for the EIS to work well.
On the upside, the autofocus works pretty intelligently, and seems to make accurate distinctions between subject and background without notable delays. And the 1,400mAh battery last a reasonably long time, somewhere between 60 and 90 minutes.
Which brings me to video quality. Though I don't expect much for $300, I admit I'm probably dinging JVC just a little harder for marketing this as an HD camcorder when it's adhering to the letter but not the spirit of the definition of HD (Canon plays the same game with its HF R series). The sensor is tiny and its native resolution is somewhat mysterious. It varies with the zoom, which is yet another trick that annoys me; it's a now-common method for gaming the zoom ranges on camcorder lenses, but it's only potentially acceptable as long as the effective number of pixels is still above the minimum needed to get a native HD capture, about 2.1 megapixels. But the HM300/320/340 and HD500's effective resolution ranges from 1.1 megapixels down to 750,000 pixels, which the camcorders then interpolate up to 1920x1080 HD.
If you're going to be playing the video at small sizes--say, 50 percent or less--it should look fine and sharp. At actual size, though, the subject is soft, and both edges and out-of-focus areas look quite smeary and processed. You can get the same results out of a cheaper standard-definition model. That's coupled with a lens that produces uncommonly bad fringing; my videos contained not just rampant purple, but yellow, cyan, and magenta variations.
However, the colors are pleasing and saturated, if not accurate, and like most low-end camcorders, the highlights tend to blow out. The sound is just OK; the mics seem oddly omnidirectional given their placement beneath the lens, and I suspect that location makes them a bit more susceptible to wind noise, the digital wind filter notwithstanding. Still, the sound is clear, if tinny.
The low-light video looks surprisingly decent, as long as you play it back scaled down. At full size it's pretty soft and noisy.
Though $300 sounds cheap for an HD camcorder, if by choice or budgetary necessity you're willing to sacrifice video quality, you might as well spend even less for a decent standard-definition model. Otherwise, I suggest you spend a little more for a true HD model like the Panasonic HDC-SD60. Of the four JVC options, only whichever is cheapest at the moment is even worth considering, and the HD500 is simply overpriced.