Panasonic Lumix DMC-GH3

Although Panasonic has developed a new Live MOS image sensor for the Lumix GH3 compact system camera, it hasn't boosted the resolution, suggesting it feels the existing 16.1 megapixels to be more than adequate. That's not to say it hasn't paid attention to resolution, though. The sensor is overlaid by a newly-developed optical low-pass filter that the company says is optimized to provide a better balance of resolution against moiré reduction.

Instead of continuing to cram in more megapixels, Panasonic says that it's worked to reduce the image sensor's noise levels, and on preventing sensor noise from entering the output signal.

A newly-developed Venus Engine image processor also has its part to play, as does the connectivity for both sensor and processor. The power supply and signal lines are designed to be as close to the same length as possible, which Panasonic says helps prevent noise entering the signal processing circuit, power supply line and grounding line. The latest-generation of Venus Engine uses both 3D Noise Reduction and Multi-process Noise Reduction algorithms in an attempt to further tame noise.

By default, the Panasonic GH3 offers a sensitivity range of ISO 200 to 12,800 equivalents, just slightly abbreviating the ISO 160 to 12,800 range of the GH2. You can now extend these in the new camera to encompass everything from ISO 125 to 25,600 equivalents, though.

Burst shooting performance has also improved a little, stepping from five to six frames per second at full resolution, and burst depth has more than doubled to 18 raw+JPEG frames. If you drop the resolution to four megapixels, you can still get an impressive speed increase to 20 frames per second, but that's only half the rate offered by the GH2 at the same resolution. Burst depth in this high-speed mode is 80 JPEG frames, enough for a four second burst.

The new sensor and processor are housed inside a die-cast magnesium alloy body, quite a step forward from the GH2, which featured a plastic shell over a stamped steel frame.

The Panasonic GH3's body is also weather-sealed, providing both splash and dust-proofing that's not present in the earlier camera.

With a tilt-swivel display and a popup flash strobe in the design, we'd imagine it's quite a task to weather-seal a camera like this, but the effort will doubtless be appreciated by users who no longer need to bother with rain covers if they're shooting with a weather-sealed lens.

The Lumix GH3's Micro Four Thirds lens mount provides access to what Panasonic says is currently (Sep 17, 2012) the largest lineup of interchangeable lenses for a digital single lens mirrorless camera

Panasonic currently has a total of 16 Lumix G and Leica DG-branded lenses, with one more slated to ship this year, but of those several are near-identical or have very similar coverage to each other.

Subtract those and you've still got around a dozen first-party options--about half zooms and half primes--not to mention those made by Panasonic's Micro Four Thirds partners.

Note, though, that the only weather-sealed options in Panasonic's lineup are the Lumix G Vario 12-35mm f/2.8 and the upcoming Lumix G X Vario 35-100mm f/2.8.

The optional battery grip is also weather-sealed, completing the system.

The GH3 offers full-time autofocus with face detection and tracking functions. Like all Micro Four Thirds cameras--and all but a few mirrorless models in general--the Panasonic Lumix GH3 relies solely on contrast detection autofocus, with no phase detect sensor available. That's no longer the hindrance it once was, though.

Panasonic claims its system to offer both better accuracy and greater performance than the dedicated phase detection systems used by typical digital SLRs. To extract the maximum possible performance from the GH3's autofocus system, Panasonic has once again increased the speed at which data is clocked off the image sensor. Where recent models have had 120 fps readout, the Lumix GH3 reads out a whopping 240 frames per second, matching the speed used by partner Olympus' FAST-branded system in the OM-D E-M5.

The Panasonic GH3's electronic viewfinder is newly-developed, and has an eyepoint of 21mm, a 100% field of view, and 0.67x magnification. A generous +/-4.0m^-1 of dioptric correction is available. An adjacent proximity sensor automatically enables the viewfinder when you bring the camera to your eye, and offers three sensitivity levels: high, low, or off.

The viewfinder is based around a 16:9 aspect Organic LED panel with an RGBG Bayer filter array, and a resolution of 873 x 500 pixels (1,746,000 dots.) Panasonic says the display has a contrast ratio of 10,000:1, and a response time of just 2.1 milliseconds. By contrast, the 800 x 600 pixel, field sequential (time-multiplexed) display in the GH2 had a contrast ratio of just 150:1, and a response time of 16.7 milliseconds.

Panasonic has also overhauled the Lumix GH3's primary display, which is also now based around an Organic LED panel. It's still an articulated, 3:2-aspect, 3.0-inch monitor, but resolution has increased slightly to 614,000 dots. That roughly equates to a 640 x 320 panel, with each pixel comprised of separate RGB dots. The side-mounted articulation mechanism allows viewing from most directions, including in front of the camera.

The Panasonic GH3's OLED monitor also retains the touch panel introduced in the GH2, but it now uses capacitive rather than resistive technology. That is the same technique used on high-end smartphones, and should translate to better sensitivity.

Also new is the Lumix DMC-GH3's built-in popup flash, which now has slightly higher strength than that in the GH2, despite offering wider coverage.

Where that camera's strobe offered a guide number of 11 meters at ISO 100, the strobe in the Panasonic GH3 has an ISO 100 guide number of 12 meters.

(Note, though, that the GH3 doesn't actually offer an ISO 100 setting. At the default ISO 200 base sensitivity, the strobe has an equivalent guide number of 17 meters.)

Coverage is now 24mm equivalent, quite a bit wider than the 28mm coverage of the flash in the Lumix GH2.

Another new addition in the Panasonic GH3 is support for wireless flash control, with a new DMW-FL360L flash strobe. We don't yet have much information on the system, except that it offers a choice of four different channels. Of course, there's still a hot shoe for external strobes, but Panasonic has now supplemented this with a PC sync terminal, making it simpler to hook the GH3 up to studio strobes. X-sync is still at 1/160 second, and flash exposure compensation is available with a wider range of +/- 3 EV range in 1/3 EV steps.

The Panasonic GH3's Mode dial is much less cluttered, with the standalone Portrait, Landscape, and Macro positions removed.

Otherwise, the selection of modes is unchanged: Intelligent Auto, Scene, Program, Aperture- and Shutter-priority, Manual, three Custom settings positions, Movie, and My Color.

There are now 23 still image and 20 movie scene modes, a significant increase from those in the GH2.

Another handy option added since the GH2 is the Lumix GH3's brand-new level gauge function.

It's a dual-axis type, which not only helps you get level horizons by balancing left-to-right roll, but also to prevent converging verticals by ensuring front-to-back pitch is neutralized too.

Metering and exposure compensation features are also unchanged.

The Panasonic GH3 determines exposures with a 144-zone multi-pattern metering system using information from the main image sensor, and provides a choice of Intelligent Multiple, Center-weighted, or Spot metering modes.

Exposure compensation is possible within a range of +/-5 EV in 1/3 EV steps, and three, five, or seven-frame bracketing is available with a step size of 1/3, 2/3, or 1 EV.

Shutter speeds for still imaging range from 1/4,000 to 60 seconds, plus Bulb. As well as a mechanical shutter, the GH3 provides an electronic shutter function.

Although white balance is mostly unchanged--Auto, five presets, Custom, and color temperature--there are now only two Custom positions, where the Lumix GH2 offered a choice of four.

Panasonic has added quite a few creative options to the Lumix DMC-GH3 that weren't present in its predecessor. These include both multiple exposure and time lapse (interval) modes, as well as a high dynamic range mode. This last option captures multiple shots and merges them in-camera to create a single image with greater dynamic range than is possible in a single exposure. We don't yet know the precise number of shots and bracketing step size used, but we do know of one very interesting difference between how Panasonic has implemented the function, and how it's done by basically of the company's rivals. When you capture an HDR image with the Panasonic GH3, the camera doesn't stop working while processing is performed. Instead, the camera multitasks, processing your HDR image in the background while allowing you to keep shooting should a photographic opportunity present itself. Very smart!

Other creative tools on offer in the Panasonic GH3 include Creative Controls and Photo Styles. The former provides a selection of 14 different filters such as Cross Process, Miniature Effect, and Star Filter that can fairly radically alter the look of your images. The latter offers a choice of six different color "looks" that provide a more subtle difference. Each can be tweaked for contrast, saturation, sharpness, and noise reduction, with an eleven-step range, and you can store the tweaked filters for later reuse.

There seems to be a surge of cameras providing for wireless connectivity with smartphones and tablets of late, and the Panasonic GH3 is the latest model to join the trend. A built-in WiFi radio provides IEEE 802.11b/g/n wireless connectivity, and in concert with Panasonic's Lumix Link application on Android and iOS devices, allows both remote control and remote live view monitoring of the GH3 body. Remotely controllable options include shutter release, focus, exposure compensation, ISO sensitivity, white balance, and photo style, among others. Of course, you can also simply transfer your data via WiFi to the connected device, whether it's a JPEG or raw still image, or a movie (even if high-def). Once on the Internet-connected smartphone or tablet, you can send your artworks to Panasonic's Lumix Club cloud service, or to social networking and sharing sites such as Facebook, Flickr, Picasa, Twitter, and YouTube. You can also view your creations from DLNA device.

While the Panasonic DMC-GH3 doesn't include a built-in GPS receiver, it is possible to geotag images as they're passed through your smartphone or location-aware tablet. The connected device's GPS or network location info is used to provide the necessary geotags.

Other connectivity includes both a 3.5mm microphone input and headphone output, a 2.5mm remote terminal, a high-definition HDMI video output (which can provide video monitoring with or without overlays), a standard-def NTSC/PAL video output (NTSC only for US cameras), and a USB 2.0 High Speed data connection. The remote terminal is compatible with Panasonic's DMW-RSL1 remote shutter release cable.

Power comes courtesy of a proprietary 7.2 volt, 1,860 mAh lithium ion rechargeable battery pack. Battery life is rated at approximately 500 frames with the Lumix G Vario HD 14-140mm f/4.0-5.8 zoom lens, and 540 frames with the Lumix G X Vario 12-35mm f/2.8 zoom lens.

We've already mentioned the weather-sealed DMW-BGGH3 detachable battery grip; here it is shown mounted on the DMC-GH3 camera body.

Panasonic will offer a couple of other new accessories alongside the Lumix GH3. These include the DMW-FL360L flash strobe (guide number 36 meters @ ISO 100; two-second fast charge; bounce head; wireless-capable; includes LED video light function), and the DMW-MS2 stereo shotgun microphone (plug-in power type; stereo / shotgun directional control switchable in menu; has shock mount to suppress camera / handling noise; includes windjammer).

No information on pricing and availability for the Panasonic Lumix DMC-GH3 or the new accessories had been disclosed at press time.