"This gives you an amazing range with each lens for video at least though I think it is useful for stills as well, especially if you are looking at stills to be used within a video project,On the GH2 this is called ETC (Extended Tele Conversion) which provides for increased "crop factor" without (or little) degradation in image quality (after all, HD videos only need 1920x1080 or 1280x720 frame size). Here's a pretty good explanation: Sometimes There Really is a Free Lunch. Unfortunately, it is not available in RAW mode for GH2 stills.
I use ETC all the time on my GH2 when videoing wildlife. Shot the following 30 sec video yesterday with a 300mm lens @ 720p. However, ETC extended the effective focal length to 300mm x 2.0 (inherent crop factor) x 3.9 (ETC) = 2,340mm 35mm equivalent.
Currently in the DSLR world, the Panasonic GH2 / GH3 cameras are the market leaders in image resolution. To get a sharper image than this you have to move up to either the $3,000 Black Magic Camera or the $6,500 Canon C100 camera...
Canon 5D Mark III vs Panasonic GH3 ( download the original MOV file to view this in full resolution ) http://vimeo.com/55060120/
Five Indie feature films shot with the GH2, one was shown at TIFF last Fall, and one has been accepted into the 2013 Sundance Festival.
All of these feature films were shot with a hacked GH2 camera. The hack is free, but it takes some research to learn how to install it. The FlowMotion ver 2.02 is my personal favorite for the GH2.
The GH3 hasn't been hacked yet, but I expect it will within the next 6 months. ( the hack requires a firmware update from Panasonic to be enabled )
I have the hack enabled on my Panasonic GF3. I bumped up the bitrate to about 24Mbps. I originally tried higher rates but my relatively inexpensive class 10 SD cards weren't keeping up.
>>>I originally tried higher rates but my relatively inexpensive class 10 SD cards weren't keeping up
You have to buy high performance SD cards to use the higher bit-rate patches.
The cheapest card that does a good job is the Patriot EP SDXC UHS-I 64GB card that sells for $47 at NewEgg.com. I use a couple of these cards and I have some SanDisk Extreme SDXC UHS-I 95MB/sec 64GB cards.
The SanDisk are better, but the Patriot EP cards are fast enough to work with almost any of the patches.