The Sony HVL-F42AM flash unit gives (alpha) DSLR photographers powerful illumination, adjustable bounce angles, wireless remote capability and intelligent features like ADI metering, auto white balance, auto zoom and high-speed sync—perfect for formal portraits, weddings and special events, still-life photography, hobby shots and more. The Freedom of Accessory Flash The Sony HVL-F42AM Flash Unit can improve formal portraits, brighten low-light scenes, bounce lighting to soften shadows and illuminate the entire frame, provide fill-in flash for backlit shots and expand your creative freedom with complex lighting effects to give shots greater depth, erase or define shadows and bring hidden details into view. More Power, Longer Range High illumination output in a small lightweight body, with effective range greater than 30 feet (10.5m) and guide number 42. (Guide number measures the illumination capability of the flash; the higher the number, the more light the unit can provide. Tested at ISO100, 105mm.) Versatile Bounce Angle Flexible adjustment angles of 90° up, 90° left and 180° right give you greater flexibility for bouncing light from ceiling, walls or bounce cards. Auto WB Adjustment Intelligent features of the HVL-F42AM include the power to adjust white balance automatically -- with color temperature information signaled to the camera before WB is adjusted. Auto Zoom Control The auto zoom coverage of the HVL-F42AM is automatically optimized for the APS-C size or 35mm full-frame size of the image sensor of the ? system camera being used (DSLR-A700, DSLR-A200 and later models). Wide-Angle Coverage The HVL-F42AM automatically adjusts flash for focal-length settings from 24mm to 105mm -- and a built-in, slide-out wide-angle panel increases wide-angle coverage to 16mm. Wireless Operation Sony cameras feature an operating mode that sends wireless signals to one or more HVL-F42AM Flash Units, allowing you to operate and adjust off-camera flash lighting setups with greater ease. High-Speed Sync Conventional flash only works well at shutter speeds from 1/125 to 1/250 of a second. The Sony HVL-F42AM Flash Unit provides High-Speed Synchronization mode that enables flash sync with shutter speeds from 1/500 to 1/4000 of a second to catch fast-moving subjects. ADI Flash Metering ADI (Advanced Distance Integration) metering capability enables the HVL-F42AM to work more effectively with lenses equipped with distance encoders -- combining TTL (through-the-lens) flash metering with guide number control calculated automatically according to the distance to the subject, the ambient light and the pre-flash reflectivity of the subject. Simple Controls, Flash Test Button Flash controls are simple and easy to operate -- and a quick-reference flash test button provides both flash ready (amber) and proper exposure (green) signals. Fast Recharging Time The HVL-F42AM Flash Unit recharges approximately 38% more quickly than Sony’s previous entry-level accessory flash (HVL-F36AM), so your system DSLR can be ready to catch the next great moment.