Panasonic G3 Flash
The Panasonic G3's built-in flash has a Guide Number rating of 34.4 feet (10.5 meters) at ISO 160. With the 14-42mm kit lens, that translates to a range of 9.8 feet at f/3.5, or 6.1 feet at f/5.6. The G3 doesn't offer an ISO 100 setting, but since most cameras don't provide an ISO 160 guide number, it's worth noting that it's flash offers a strength equivalent to 8.3 meters at ISO 100. That's quite a bit weaker than most digital SLRs, which are typically rated at 12 or 13 meters, but a little stronger than the popup strobes in some smaller compact system cameras, which can have guide numbers as low as 6 meters.
The Panasonic G3'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 Micro Four Thirds lenses could cast a shadow when the lens hood is attached. The Panasonic G3's flash is disabled by pressing down until it clicks shut.
The Panasonic G3'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 either the Quick menu, or an option on Page 2 of the Record menu, 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. For slow-sync exposures, both first and second curtain synchronization modes are provided. 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 G3.
The Panasonic G3 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 G3 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 G3'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. Slightly above average positive exposure compensation required.
|14mm, f/3.5||42mm, f/5.6|
Coverage. Flash coverage is rather uneven at wide-angle, leaving the corners of our flash target image darker at 14mm, thought that's not unusual. Some of the corner shading can also attributable to the lens itself. Coverage is more uniform at full telephoto (42mm), but a little dim at ISO 160.
Exposure. Indoors under incandescent background lighting, the Panasonic G3's flash performed reasonably well, but required a flash exposure compensation of +1.0 EV for a bright image, which is slightly more than the average of +0.7 EV normally needed 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 reasonably bright at 6 feet at wide-angle, but was much brighter at 7 feet. Brightness decreased gradually with distance from there. Exposure was still fairly bright up to about 11 feet, though, and flash images were still usable up to about 13 feet. At full telephoto, flash exposures started out slightly dim at 6 feet and brightness fell off rapidly after 7 feet. Keep in mind the G3's base ISO is 160, so flash range is not directly comparable to cameras that have a base ISO of 100.
|Manufacturer-Specified Flash Range|
Manufacturer-Specified Flash Range Test. As mentioned previously, Panasonic rates the G3's flash with a Guide Number (GN) of 10.5 meters at ISO 160. That works out to about 7.5 feet at an aperture of f/4.6 which we used for our test shot above. The Panasonic G3 produced a good flash exposure at the rated distance, just a hair dimmer than ideal (only about 0.1 EV underexposed). Our standard test method for flash range uses a fixed setting of ISO 100 (ISO 160 for the G3), 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.