When Panasonic first launched the GH1, its second Micro Four Thirds camera, it was widely seen as simply being a G1 with video shooting and a considerably more expensive kit lens. And, if your primary concern was stills photography then this wasn't an entirely unreasonable assessment. However, its real appeal was not that it had video, but that it offered what was, at the time, some of the most flexible, high quality video available. Again, the 14-140mm F4.0-5.8 kit zoom may not have been cheap but it had been specifically designed and built with fast, quiet autofocus and stepless aperture control to allow AF during movie shooting and exposure changes without sudden changes in brightness.
Now that the G2 (along with the majority of contemporary cameras) is able to capture HD video, the distinctions between just being able to shoot HD and to really control it become more apparent. Stills shooters may get some advantage from the new, higher resolution sensor but the main differences between the GH2 and G2 are the ability to control the movie shooting process (both in terms of frame rate and shutter speed).
In the years since Olympus and Panasonic jointly announced the Micro Four Thirds standard there have been eight models launched to date, seven of which share the same 12MP sensor. The only exception was the GH1 which, despite its 12MP output actually featured a 14MP sensor. The sensor was slightly larger than the format's imaging circle, which allowed it to deliver images in different aspect ratios while retaining the same image diagonal. And now the GH2 follows the same pattern, shooting 16MP images using its brand-new, similarly over-sized 18MP sensor.
This sensor is capable of much greater readout speed (120Hz) than its predecessor, bringing a host of benefits. Videographers will see an improvement in the quality of the highest quality output - the 1080i output is derived from 60p or 50p capture, rather than doubled-up from 24p or 25p on the GH1. The faster readout also means the AF system can more frequently check the accuracy of its focus, which promises faster autofocus (on lenses that can respond quickly enough). Finally, the faster readout means the live view is updated 60 times a second (rather than 24fps displayed at 60hz), giving a smoother viewing experience with less tearing.
The electronic viewfinder has also been slightly widened - it now shows 852 x 600 pixels as opposed to 800 across - which allows it to display 16:9 and 3:2 previews without the need for such extensive cropping as before.
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| The G2 alongside one of its current nearest competitors - the Canon EOS 60D. Although it follows conventional DSLR styling, the considerably smaller size and bulk of the GH2 is obvious in this view - one of the advantages of a mirrorless and (comparatively) smaller sensor design. |
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Compared to GH1 - key differences
The GH2 might look very similar to its predecessor at a casual glance but there are some major differences between the two models. Let's have a look at the main changes:
- New sensor - multi-aspect Live MOS with 18.3 million total pixels
- ISO range 160 - 12800 (vs 100-3200)
- Sensor capable of 1080p video at 60 or 50 fps (rather than 24 or 25 fps), still output as 60i/50i
- Faster sensor read-out promises faster AF and smoother viewfinder image (less tearing)
- Larger EVF coverage to match multi-aspect shooting (852 x 600 rather than 800 x 600 pixels)
- Touch-sensitive LCD screen (same as G2)
- New, more modern looking menu screens
- G2-style combined AF mode/pattern control on top plate
- Direct movie shooting button moved to top plate from rear of camera
- Control dial moved from front of handgrip to rear of camera
- Dedicated metering and 'film mode' buttons replaced by highly customizable Fn buttons
- Q menu button moved from top plate to rear of camera
- New battery (DMW-BLC12E) with fractionally smaller capacity (1200mAh vs 1250mAh)
- Slightly heavier (394g compared to 385g body only)
Key feature comparison (vs G2 vs GH1)
Like the GH1, the GH2 is distinguished from its G-series contemporaries by its video shooting capabilities. The GH2 is a far more serious video shooting tool than the G2, and indeed the majority of its competitors - both mirrorless and DSLR. The GH2 offers a similar video specification to the GH1 but with one important difference - the sensor no longer doubles-up its sensor output in order to create its highest-speed video (the GH1 sensor could capture at 24 or 25 fps, which was then put out as 60i or 50i footage). Instead, the latest sensor can capture progressive (whole frames) at 60 or 50 fps. Its output is still limited to 60i or 50i because there are no common ways to distribute 60p or 50p footage, but this should certainly improve the output quality. In its 'Variable Movie Mode' the GH2 also has the ability to save footage at a different frame rate from the one captured - allowing slow-motion or high-speed effects.
From a still photography point of view the GH2 brings very little that is 'new' to the G-series apart from its increased resolution - up to 16MP from 12.1MP. This makes the GH2 the highest resolution camera in Panasonic's Micro Four Thirds range, and a maximum ISO of 12,800 makes it (at least on paper) the most versatile too. Like the G2, the GH2's LCD screen is touch-sensitive, but also like the G2, it is not 'mandatory'. In other words, GH1 users upgrading to the GH2 with no interest in experimenting with the touch technology can more or less ignore it if they wish. (Unfortunately, though, it doesn't share the GF2's new 'designed for touch' interface.)
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| From the front, the main difference between the GH2 and G2 is that the former is slightly taller, and more of a 'classic' SLR shape. The G2 is a noticeably squatter when viewed in direct comparison, but the family resemblance is unmistakable. |
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| From the top, the GH2 is very similar to the G2. The most obvious difference is the stereo microphone which dominates the top of the flash housing of the GH2 (the G2 makes do with a single, tiny mic aperture just forward of the AF mode switch). Both cameras have a button for direct movie shooting, but whereas the G2 has a dedicated iA mode button, in its place the GH2 has a customizable 'Fn' button. |
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Compared to: G2 and GH1
 Panasonic GH2  |
 Panasonic GH1 |
 Panasonic G2 |
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| Sensor | • 4/3 type MOS ('Live MOS sensor') • 18.3 million total pixels • 16.0 million effective pixels • RGB (Primary) color filter array |
• 4/3 type MOS ('Live MOS sensor') • 14.0 million total pixels • 12.1 million effective pixels • RGB (Primary) color filter array |
• 4/3 type MOS ('Live MOS sensor') • 13.1 million total pixels • 12.1 million effective pixels • RGB (Primary) color filter array |
| Sensitivity | ISO 160-12800 in 1/3EV steps | ISO 100-3200 in 1/3 EV steps | ISO 100-6400 in 1/3 EV steps |
| Movie mode | • AVCHD : 1920 x 1080p 24fps (Approx 23 or 17 Mbps) 1920 x 1080i 60fps (Approx 17 or 13 Mbps) 1280 x 720p 60fps (Approx 17 or 13 Mbps) • Motion JPEG: 1280 x 720, 30fps 848 x 480, 30fps 640 x 480, 30fps 320 x 240, 30fps |
• AVCHD : 1920 x 1080, 24fps (24 fps encapsulated in a 60i format) 1280 x 720 (60 fps) • Motion JPEG: 1280 x 720, 30fps 848 x 480, 30fps 640 x 480, 30fps 320 x 240, 30fps |
• AVCHD Lite: 1280 x 720, 60p (from 30fps sensor output) 1280 x 720, 50p (from 25 fps sensor output) • Motion JPEG: 1280 x 720 (30fps) 848 x 480 (30fps) 640 x 480 (30fps) 320 x 240 (30fps) |
| LCD monitor | • Touch sensitive 3.0" TFT LCD monitor • Multi-angle swing and tilt (180° swing, 270° swivel) • 460,000 dots • Approx 100% frame coverage |
• 3.0" TFT LCD monitor • Multi-angle swing and tilt (180° swing, 270° swivel) • 460,000 dots • Approx 100% frame coverage |
• Touch sensitive 3.0" TFT LCD monitor • Multi-angle swing and tilt (180° swing, 270° swivel) • 460,000 dots • Approx 100% frame coverage |
| Microphone | • Built-in stereo
• Socket for external mic |
• Built-in stereo • Socket for external mic |
• Built-in monoaural • Socket for external mic |
| Dimensions | 124 x 90 x 76 mm (4.9 x 3.5 x 3 in) |
124 x 90 x 76 mm (4.9 x 3.5 x 3 in) |
124 x 84 x 74 mm (4.9 x 3.3 x 2.9 in ) |
| Weight (body only, no card/battery) | 394 g (13.9 oz.) | 385 g (13.6 oz.) | 370 g (13 oz.) |
Multi-Aspect Sensor
Like the Panasonic LX5 and the GH1 before it, the GH2 uses a multi-aspect ratio sensor. It's slightly larger than usual for Four Thirds, and at any given aspect ratio (even at 4:3) the camera only uses a crop from the total available sensor area. |
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| 4:3 | 3:2 | 16:9 | 1:1 |
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At first sight this may seem strange but the result is that the lens offers the same diagonal angle of view regardless of selected aspect ratio, making it much easier to get a feel for the behavior of the lens. It also means you make the most of the sensor area, getting similar pixel counts in all modes.
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