Canon Speedlite 220EX review
Designed for automatic operation only, the 220EX Flash Unit excels at
providing natural-looking balanced flash exposures. When attached to the
EOS Elan II, Elan IIe, or EOS Rebel G, the 220EX incorporates the superior
technology of Canon’s unique E-TTL evaluative pre-stored flash
exposure control system, FE Lock for a new dimension of creative control
and FP Flash (High Speed Sync) for flash photography up to maximum shutter
speed. When used with other EOS cameras, or the T90, it operates as a TTL
autoflash (off-the-film flash metering.) When in E-TTL operation, flash
exposure is measured and controlled by the camera in combination with
Canon’s AIM system. Subject position, ambient light level, evaluative
metering and pre-flash data are instantly analyzed, including heavy
backlighting or reflections from background windows or mirrors.