This page is a collection of links to information related to the movie / video capture mode on the Panasonic Lumix DMC-GH1.
I’ve also compiled movies / video samples.
This should help in determining if the video quality of the GH1 meets your expectations.
Full attribution is given by linking to the source and where available, the author’s homepage or photo gallery.
More on the Codecs
In a forum post, LizaWitz explains about the codecs used by the GH1:
The 1080/24p is really 1080/24p. Its just stored in a 60i stream, which means you do a lossless pulldown before editing. You get real 1080/24p, with NO interlace artifacts. Its stored in the 60i stream to give you live HDMI out while capturing (without having to put two codecs in there doubling the workload of encoding to both formats.) It does this by splitting the progressive frames into fields and then duping one of them to fit the 60i timing— but the images are captured all at once, not interlaced, and so when they are recomposited, you have no artifacts.
Official Movie / Video Samples
The official page for Panasonic GH1 movie / video samples has several clips of reduced resolution.
The footage of a dog running towards an airborne frisbee is especially impressive as it showcases the continuous AF (autofocus) at work.
The clip with the seagulls has audio, I find the sound is crisp and clear.
The same page has details on the technology behind the video recording mode, among others, AVCHD (Advanced Video Codec High Definition), and the built-in stereo microphone that features Dolby Digital Stereo Creator.
The description on the page also suggests that you get full control over shutter speeds and aperture during movie recording. In comparison, the Nikon D90 only lets you control aperture within a certain range, while the Canon 5D Mark II doesn’t give you any control over the exposure parameters without resorting to tricks and workarounds.