Panasonic GH2 Review
Panasonic GH2 Flash
The Panasonic GH2's built-in flash has a Guide Number rating of 45.6 feet (13.9 meters) at ISO 160, translating to a range of about 11.4 feet at f/4 and 7.9 feet at f/5.8 with the kit lens. That's the same power as the GH1's 36 feet (11 meters) flash at ISO 100, but the GH2's base ISO is 160. The GH2's flash is little weaker than most digital SLRs, which are typically rated at 12 or 13 meters at ISO 100, but much stronger than the GF2's smaller flash, which has a GN of only 20 feet or 6 meters at ISO 100.
The Panasonic GH2's flash is released manually by sliding the Flash Open switch on the camera's top panel forward. Raising the flash enables it. It never pops up automatically like some models, which can be good or bad, depending on your point of view. A novice would probably appreciate an auto-pop-up flash, but someone with experience might think it a nuisance.
When open, the flash doesn't extend very high, so at wide angle longer lenses could cast a shadow, especially when a lens hood is attached. The Panasonic GH2's flash is disabled by pressing down until it clicks shut. The Panasonic GH2 has a dedicated AF assist LED which Panasonic rates as having a range of up to 9.84 feet (3 meters) at wide-angle with either the 14-140mm or the 14-42mm kit lens. AF assist can be disabled in the Custom menu.
The Panasonic GH2's built-in flash has seven modes: Auto, Auto with Red-Eye Reduction, Forced On, Forced On with Red-Eye Reduction, Slow Sync, Slow Sync with Red-Eye Reduction, and Forced Off. Flash modes are changed via the Record or Quick menus, and available settings vary depending on exposure mode. The flash is forced off when closed. A Digital Red-Eye Reduction feature is offered, which when enabled, will attempt to remove red-eye after the photo is taken, via post-processing. A second curtain synchronization mode is also offered. X-Sync (the maximum shutter speed with the flash enabled) is 1/160 second, a bit below average these days, and there is no mention of a higher-speed FP (focal plane) mode. There's also no wireless flash support in the Panasonic GH2.
The Panasonic GH2 allows you to adjust flash and ambient exposure independently of each other, by providing flash exposure compensation between -2 and +2 EV in one-third EV increments. Flash exposure bracketing is not supported, and there is no manual flash mode where output level can be set as a percentage of full power.
Like an SLR, the Panasonic GH2 also has a dedicated hot shoe for mounting external flash units, like Panasonic's DMW-FL500, FL360, and FL220. Olympus flash units such as the FL-50, FL-36, FL-20, and FL-14 should also work, and non-dedicated units can also be used provided they have a compatible trigger voltage and polarity. (Panasonic does not seem to mention the trigger voltage or polarity in the GH2's user manual, though they do warn against using an external flash with "high-voltage" or reverse polarity.)
The advantages of a good external flash are many: more power for increased range, faster recycle times, longer battery life, reduced red-eye, auto zoom to match coverage to the current focal length, and the ability to adjust the tilt and swivel of the head to allow light from the flash to be bounced off nearby surfaces such as a ceiling, for a diffuse effect. Most external flash units have a more powerful AF assist illuminator built-in than the one on the body, and other useful features such as modeling flash are common on higher end models.
Flash Test Results
Coverage and Range
A moderately powerful flash, but with uneven coverage at wide angle. Average positive exposure compensation required.
Coverage. Flash coverage is rather uneven at wide angle, leaving the corners of our flash target image dark at 14mm. The relatively large lens also casts a shadow at the bottom of the frame in our wide-angle coverage shot, even without a hood attached. Coverage is more uniform at full telephoto (140mm), but was very dim at ISO 160 as expected for such a long zoom, so the shot top right was taken at ISO 800.
Exposure. Indoors under incandescent background lighting, the Panasonic GH2's flash performed well, requiring exposure compensation of +0.7 EV for a bright image, which is about average for this shot. The camera's slow-sync flash mode required no compensation, though the longer shutter time results in a much warmer cast from the ambient background lighting.
ISO 160 Range. Flash exposure started out bright at 6 feet at wide angle, but decreased gradually from there. Exposure was still usable up to about 9 or 10 feet. At telephoto, flash exposures started out slightly dim at 6 feet, got slightly brighter at 8 and 9 feet, then stared to fall off at 10 feet and beyond. Keep in mind the base ISO is 160, so range is not directly comparable to cameras that have a base ISO of 100.
|Manufacturer-Specified Flash Range|
Manufacturer-Specified Flash Range Test. Panasonic rates the GH2's flash with a Guide Number (GN) of 13.9 meters at ISO 160. That works out to about 11.4 feet at an aperture of f/4 and 7.9 feet at an aperture of f/5.8. In the shots above, the Panasonic GH2 produced good exposures at both wide-angle and telephoto ends. The wide-angle shot was just slightly overexposed (by about 1/7 EV) and the telephoto shot was dead on. Good results here, though we don't know why the 11 foot wide-angle exposure in our Flash Range series was significantly dimmer. It could be that the GH2 indicates the flash is fully charged when in fact it isn't. Our standard test method for flash range uses a fixed setting of ISO 100, to provide a fair basis of comparison between cameras. We've now also begun shooting two shots using the manufacturer-specified camera settings, at the range the company claims for the camera, to assess the validity of the specific claims.
Note: For details, test results, and analysis of the many tests done with this camera, please click on the tabs at the beginning of the review or below.