More than any other camera I've reviewed lately, my opinion formation about the Panasonic Lumix DMC-GH1 inevitably comes back to price. It's fast, but not as fast as other cameras that cost a lot less. It has great photo quality, but its high ISO sensitivity photos don't match that of comparably priced (or cheaper) dSLRs. It supports video capture, and delivers the most camcorder-like recording experience I've seen to date from a still camera. However, does the interchangeable lens capability for video make it worth the price of a comparable HD camcorder, especially since there's currently only one video-optimized lens available?
The GH1 ships with the Lumix G Vario HD f4-5.8 14-140mm lens. Though the camera body is compatible with all Micro Four Thirds lenses, as well as Four Thirds lenses via an adapter, only the HD lenses support continuous autofocus during movie capture and they are designed to focus more quietly than standard lenses. We also tested the camera with the new 7-14mm f4 lens, which isn't stabilized and not video optimized. (Here's a complete list of lens compatibility for the G1 and GH1.) I like the lenses quite a bit, but couldn't help wishing they had slightly wider maximum apertures and could focus more closely.
With a design identical to its lower-end sibling, the G1, the GH1's 15.2-ounce body, with dimensions of 3.3 inches high by 4.9 inches wide by 1.8 inches deep, is overall lighter and more compact than most midrange consumer dSLRs. It's made of sturdy plastic with some metal on the inside and on the mounts, with a nice-feeling rubberized coating over everything. It also has a large, comfortable grip, and offers a considerable number of direct-access button and dial shooting controls; I generally like their layout and operation.
There's an onscreen Quick Menu for accessing settings from a central location: white balance, ISO sensitivity, AF mode (face detection, AF tracking, 23-area AF, and single-area AF), metering (multi, centerweighted, and spot), Intelligent Exposure (low, standard, high, and off), flash, video and still image size and quality, self-timer, image-stabilization mode (active, on prefocus, and y-axis only) used in conjunction with the optically stabilized lens, and film simulation mode (standard, dynamic, nature, smooth, nostalgic, vibrant plus black-and-white versions of standard dynamic and smooth). The main navigation control is a jog dial that lies under your forefinger on the grip; depending upon what mode you're in you either press and scroll with it or simply scroll with it. I found it awkward when I was testing the G1; this time around, it didn't get in my way as much.
If you don't want to use the full onscreen display, you can also set the camera to display the settings around the edges of the screen and cycle around them that way. You can also set the camera so that the EVF display mimics the menu display, though you can't display settings on the LCD while viewing the scene through the EVF.
For video, you can set encoder type (AVCHD or Motion JPEG MOV files), quality (24fps 1080p at 17 megabits per second, 30fps 720p at three different bit rate choices, and various lower resolution options), metering, four levels of Intelligent Exposure, and four levels of wind filtering. While AVCHD is a more efficient encoder than Motion JPEG and you can record up to the capacity of the card, the AVCHD MTS files need to be transcoded before you can post them online or send them around to friends. (Panasonic provides two somewhat conflicting guidelines on SD card speed for movie recording: online it recommends 10 megabytes per second minimum, while in the manual it suggests a Class 6 card, which is 6MB per second minimum.)
There's a dedicated button for movie capture, so you needn't go into a specific video mode, but if you want to be able to set shutter speed and aperture or use exposure compensation, you will need to use the Creative Movie mode. The one disappointment here is that you can't drop the shutter speed below 1/30 second. That's fine for playing with depth of field--enabling faster shutter speeds allows larger apertures for a given exposure--but not for slow shutter speed effects.