Combining the strengths of its predecessor 550EX while providing additional functions at higher speeds, the Speedlite 580EX is Canon's new flagship flash unit featuring a higher maximum guide number, shorter recycle time, autozoom control for image sensor size, and design improvements for easier handling by digital SLR users ranging from professional to advanced amateur.
Faster Recycle Time for Quick Shooting plus E-TTL II Flash Metering - Thanks to modifications to the battery contacts and recharging circuit, the recycle time of the Speedlite 580EX has been made *25-percent shorter than available with the 550EX.
Improved Styling and Functionality- Reducing width by 4mm and weight by 30g, the Speedlite 580EX matches sophistication with handling ease. The flash head's built-in wide panel expands flash coverage to suit wide-angle shots of 14mm angle of view. A catchlight panel generates a weakened light toward the subject for lively portraits when extended and the wide panel retracted.
Flash exposure control system, wireless flash control with multiple Speedlites, and even distribution of light over the zoom range are retained. One new function is the expanded range of the AF-assist beam, compatible with all EOS AF cameras, including the EOS 20D. Left-right 180-degree bounce, one-touch bounce lock release, and improved controllability for greater exposure stability are among the upgraded functions.
Auto conversion of flash coverage plus Color Temperature Information Transmission with Compatible Digital SLRs - When the Speedlite 580EX receives image size data from a supported EOS digital camera*, the flash head automatically zooms to match the effective angle of view. The resulting flash coverage is more accurate. When color temperature data is automatically transmitted from the Speedlite 580EX to a camera*, the camera sets the color balance for the optimal flash shot.
* EOS 20D, EOS-1D Mark II (firmware update necessary) or later camera models
Newly Designed Select Dial with Left-right 180-degree Bounce - The newly adopted Select dial simplifies the main operation interface from holding down the + or
Comments about Canon 580EX Speedlite Flash:
This is a great flash for professionals and hobbyists alike. It has great power and recycle time. It will not recycle at the 12f per sec that your shutter can, but I've never had a problem with recycling - except once at a wedding reception where I'd been shoot all day and forgot my back up batteries - that was MY issue, not the flash.