The GH3 includes a built-in flash with Guide Number 12 (m, at ISO 100), which gives it a maximum range of 17m at the camera's native ISO of 200. Disappointingly, the fastest shutter speed with which flash can be used while giving full illumination is just 1/160th of a second. Flash is not available in combination with electronic shutter.
The GH3 is the company's first camera to offer remote control of off-board flashguns, wirelessly. Set the camera to wireless flash in the menus and you gain the ability to independently control up to four groups of flashguns.
|Flash exposure is pretty good. The exposure has come out well and retained a convincing skin tone.|
The GH3 can also capture multi-image HDR images. Like most of the camera's other multiple exposure modes this option is only available when shooting JPEGs, and won't retain the files used to create the final image.
There are two parameters that can be set for shooting HDR images - the extent of exposure difference from the metered value (+/-1EV, +/-2EV, +/-3EV and Auto), and an auto-align option. The extent options give a good degree of control - it's hard to incorporate more than the +/-3EV setting's additional 6EV into an image without the result looking flat and washed-out, so we suspect anyone wanting more will prefer to bracket their exposure and process the results themselves.
However, the auto-align option is something of a disappointment. Whereas we've seen Sony's HDR system improve to the point that it is really very good at identifying and removing duplicate data from the multiple exposure, the GH3 is much more prone to including fragments of the same object from each of its exposures, regardless of the Auto-Align setting. Furthermore, to give itself some flexibility to align images, the Auto-Align function crops around 7% off the image edges, then magnifies the central section back up to the full pixel count. Overall, we didn't find the HDR function terribly useful.
The GH3 also has a time lapse feature that allows you to leave the camera shooting. You can either set it off immediately or at a preset time. The camera saves all the original files (which can include Raw files). It will play the sequence back as a movie from within the camera but it won't save this movie to a file.
|A 120-frame timelapse, shot at 30 second intervals. Frames combined using PhotoFunStudio. Playback speed then increased in Final Cut Pro X (not supplied).|
The supplied PhotoFunStudio software does allow you to combine and output these timelapse sequences as movies (either MP4 or MOV), but only allows you to output at a rate of 1 frame per second, so you'd need to use another piece of software to control the playback rate, as we've done here. The software depends on an EXIF tag created by the camera to recognise which images are part of a sequence, so it's not easy to add or subtract images in your videos.
Multiple Exposure mode
The GH3 includes the option to combine multiple exposures into single images. You have a number of controls - including the ability to either shoot on top of an existing image or start with the next image you take. The camera offers the existing image overlaid on top of live view, so that you can preview your composition and you can choose whether to average or combine the brightness of the images you shoot.
The camera does its best to let you get the results you want, but it's a little hard to understand why you'd attempt to do in-camera something that can be so much better controlled in software, when you get back to a computer. Unusually, the camera will allow you to create composite Raw files. Ultimately, though, we're not entirely convinced this is a mode that you need in camera, given how much more control you gain in terms of alignment and blending by using processing software.
The usable dynamic range of a camera when shooting in Raw is mainly defined by how much additional detail can be pulled out of the shadow regions. Here we've processed our standard studio scene with +3EV of exposure compensation to see how cleanly extra detail can be pulled out of the shadows.
|Panasonic DMC-GH3 ISO 200: ACR +3EV, NR off||100% crop|
|Panasonic DMC-GH2 ISO 160: ACR +3EV, NR off||100% crop|
|Olympus OM-D E-M5 ISO 200: ACR +3EV, NR off||100% crop|
|Nikon D7100 ISO 100: ACR +3EV, NR off||100% crop|
The GH3 shows very little improvement over the GH2 and essentially no difference from the OM-D, suggesting there's no great well of additional dynamic range to dip into, if you're processing from Raw. The results are still clean enough that you could get away with pulling an extra couple of stops of detail out of the shadow regions of your images without having to worry too much about noise (these examples have NR turned right down), but the D7100 provides much greater leeway in that respect.
Overall Image Quality/Specifics
The GH3's JPEGs produce better color than we've seen before from Panasonic cameras - yellows aren't so green and white balance seems to be less cool than previous models. They're not quite as pleasing as those from the Olympus E-M5, but there's little to complain about.
|The GH3's color response isn't quite as pleasant as some of its rivals - its yellows in particular can be a touch muted with a slight green tinge.|
Image detail is good too - the context-sensitive noise reduction at low ISOs means the output tends to be a touch 'cleaner' than default Raw processing but retaining plenty of fine detail. Furthermore, we've found it hard to improve on the camera's sharpening in terms of emphasizing detail. We can get similar amounts of detail with fewer sharpening artefacts but, at low ISO, the GH3's output is very pleasant.
|Even with careful sharpening in Photoshop, we couldn't get significantly more detail out of low ISO images. The crop on the right shows plenty of well-defined detail without looking over-sharpened.|
At High ISO the story is less positive, with blotchy and rather heavy-handed noise reduction making JPEGs less and less usable as the light drops and you start to push the ISO up. However, there's still a good amount of detail in the files if you process from Raw, though fine banding starts to appear at the highest settings.