Sony DSLR-A550 Flash
Sony A550 Flash
The Sony A550 features a built-in, pop-up flash, which operates in either Auto, Fill-Flash, Slow-sync, Rear Sync, Wireless, and Flash-off modes. To release the flash from its compartment, press the button on the left side of the pentamirror housing. Close it again by pushing the flash head back down.
The Flash mode is changed from the Function screen. In Auto flash mode (available only in the camera's Auto or Scene Selection modes), the camera automatically determines when to fire the flash based on the existing lighting, and will pop-up the flash automatically. In Fill-Flash mode, the flash fires with every exposure, regardless of lighting conditions. Slow-sync mode fires the flash for foreground fill exposure, while allowing the background to "burn in". The Rear Flash Sync mode fires the flash at the end of the shutter time, rather than the beginning. If you have moving objects in the scene with lights, as with a car, this will produce a sharp image of your subject, with a "motion trail" following behind it when shooting at slower shutter speeds. The flash is off when Flash Off mode is selected, or when the flash is down in non Auto exposure mode.
A Flash control option in Record Menu 1 allows you to select between ADI and Pre-Flash TTL. The only difference between the two is ADI takes into account focus distance information from the lens, which can make for more accurate flash exposures, especially with highly reflective subjects. A Red-Eye Reduction option is available through the Custom 1 menu. When Red-Eye reduction is enabled, the camera will fire a few low-power flash pulses before it actually snaps the picture, to make the pupils of your subjects' eyes contract.
Flash exposure compensation can be set via the Camera 1 menu, measuring two stops lower or greater, in 1/3-stop increments. This is in addition to standard exposure compensation.
The A550's built-in flash has a Guide Number (GN) of 12 meters or 39.4 feet at ISO 100. That's about average for the Consumer SLRs we've tested. Maximum sync speed is 1/160s. High Speed Sync (HSS) shooting with shutter speeds up to 1/4000s is available with Sony HVL-F58AM and HVL-F42AM external flash units.
The A550 also has a top-mounted hot shoe for attaching an external flash unit. The shoe design and contact arrangement are set up for Sony's own dedicated flash units. As is usually the case for consumer SLRs, no PC-sync terminal is provided.
The Wireless mode lets the Sony A550 work with compatible remote flash units with wireless capability, specifically the Sony HVL-F58AM and HVL-F42AM. Four separate control channels are available for wireless operation, to allow multiple photographers to work wirelessly in the same area without interfering with each other. You're limited to a single external flash unit vs the 3 groups that you can control with Sony's higher-end models, but it still opens a lot of creative possibilities, when the flash doesn't have to be attached to your camera. Operating in Wireless mode with a compatible external flash unit, the Sony A550's flash exposure compensation adjustment can adjust the intensity of the external flash remotely, once the camera and flash unit have been initially synced to each other.
Flash Test Results
Coverage and Range
Very good flash range with somewhat uneven coverage at wide-angle. Our standard shot required less than average exposure compensation.
Coverage. Flash coverage was uneven at wide-angle (18mm), but much more uniform at telephoto (55mm). Uneven coverage at wide-angle isn't unusual, though.
Exposure. The Indoor Portrait test scene was bright without having to use any exposure compensation. (Most cameras we've tested required about +0.7 EV for this scene.) The camera's Slow-Sync flash mode produced bright, even results with +0.3 EV compensation, though with a stronger pinkish-orange cast from the room lighting.
ISO 200 Range. We normally test flash range using ISO 100, but the Sony A550's minimum ISO sensitivity is 200. With the 18-55mm kit lens, flash exposure started out very bright at 6 feet at wide-angle and remained quite bright up to about 10 feet, where it started to decrease gradually as distance increased. Flash images were still bright all the way out to 16 feet, though. At full telephoto, flash exposures also started out quite bright at 6 feet, peaked in brightness at 8 or 9 feet, but flash exposure became somewhat inconsistent from there, sometimes resulting in very bright images (12 and 14 feet) and other times in dim images (13 and 16 feet). Flash exposure was still quite bright at 15 feet, though. Good if somewhat inconsistent results here, but keep in mind results are not directly comparable to cameras that have a base ISO of 100. (ISO 200 provides roughly 1.4x the flash range as ISO 100.)
|Manufacturer-Specified Flash Range|
Manufacturer Specified Flash Test. The Sony A550's built in flash is rated with a Guide Number of 12m at ISO 100. That works out to about 15.9 feet at f/3.5 and 9.8 feet at f/5.6, the maximum apertures of the kit zoom lens. In the shots above, the Alpha 550 performs as Sony says it will, producing a good exposure at the rated distance with its ISO set to 200 at wide-angle, though results are actually a little too bright at full telephoto. 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.