Produce the Flash You Want 1. Flash exposure compensation Combining flash exposure compensation and exposure compensation. E-TTL autoflash is a ground-breaking flash system which obtains natural-looking flash pictures like never before. Moreover, flash exposure compensation for finer adjustment of flash output level is also available. By combining it with normal exposure compensation, you can create your own lighting, balancing the ambient light and flash as desired. 2. Manual flash and catchlight Manual flash mode to control the flash freely. By setting the 550EX to the manual flash mode, you can set the flash output anywhere from 1/128 to 1/1 (full) output in full-stop increments. This photo was taken with the minimum flash output of 1/128 so that the effect of the natural light would not be lost. As was intended, a catchlight was created in the girl's eyes and the details of her clothes and oranges could be shown. 3. FEB (Flash Exposure Bracketing) FEB changes the flash exposure while keeping the background exposure the same. The correct exposure as determined by the camera may not always be what you want. With the 550 EX's FEB, the flash directed at the subject changes automatically for three consecutive frames while the background exposure remains the same. The flash is bracketed in the following sequence: Correct exposure, underexposure, and overexposure. The flash bracketing amount can be set up to -/+3 stops in 1/3-stop increments (1/2-stop increments with certain EOS cameras). Obtain the flash exposure you want without hassle. 4. Automatic flash reduction control All EOS cameras have a built-in program called "automatic flash reduction control" that varies flash exposure level according to ambient light level. It applies standard flash exposure (no compensation) in dark conditions, and reduced flash exposure in bright conditions. This program was designed to provide natural looking flash fill in most bright conditions, so that even a beginner without experience could achieve pro-quality results. However, any flash exposure compensation set by the user on the camera or Speedlite is applied on top of, not instead of, automatic flash reduction control. This may cause unexpected results in bright conditions unless the automatic flash reduction is taken into account. Some EOS cameras* are equipped with a Custom Function** which shuts off automatic flash reduction control, thus applying a standard flash exposure level in any lighting condition. We recommend the use of this Custom Function for anyone who plans on applying their own flash exposure compensation settings, since it allows greater control of the results. Note that this Custom Function is not available for any past or present EOS camera other than those listed below. *(EOS-lN, EOS-1N RS, EOS D2000, EOS-DCS series, EOS-3, and EOS 5/A2/A2E) **(CF-14-1 for the EOS-3 and models based on the EOS-lN, or CF16-1 for the EOS 5/A2/A2E) << Back to Main . 1 . 2 . 3 . 4 . 5 . 6 . 7 . 8 .