Monday, January 29, 2007
Lighting The Way
Understand the fundamentals of flash to make the best purchasing decision
Even nondedicated (non-TTL) slave flash can be used, such as the Nissin Digislave or Phoenix D91-BZS. They're an affordable alternative for achieving a multiple-flash setup.
The top flash sync of a camera has typically ranged from 1⁄125 to 1⁄250 sec. A few models even provide a flash sync as high as 1⁄500 sec. This is the top shutter speed that ensures that the flash illuminates the entire image sensor. Too fast of a shutter speed results in the shutter partially obstructing the CCD at the moment of exposure.
High-speed sync allows shutter speeds as high as 1/8000 sec., a great benefit when you want to perform fill-flash under bright conditions. When using flash under such lighting, the background is commonly overexposed, because with normal flash sync, the shutter speed would be no higher than 1/250 sec. To avoid overexposure, the lens might need to be stopped down to its minimum aperture, ƒ/22, for example. You may not always want to use such a small aperture, however.
High-speed sync allows the use of higher shutter speeds by emitting light in the form of rapidly repeating flash bursts barely perceptible to the human eye. Although the effective range of the flash is reduced, it provides the means to use fill-flash and wider apertures under bright conditions.
|Canon (800) OK-CANON||www.usa.canon.com|
|Konica Minolta Photo Imaging USA (877) IMAGING||www.konicaminolta.us|
|LumiQuest (830) 438-4646||www.lumiquest.com|
|Metz (Bogen Imaging Inc.) (201) 818-9500||www.bogenimaging.us|
|Nikon (800) NIKON-UX||www.nikonusa.com|
|Nissin (THK Photo Products) (800) 421-1141||www.thkphoto.com|
|Novoflex (HP Marketing Corp.) (800) 735-4373||www.hpmarketingcorp.com|
|Olympus (888) 553-4448||www.olympusamerica.com|
|Pentax (800) 877-0155||www.pentaxusa.com|
|Phoenix Corp. (800) 729-7846||www.phoenixcorp.com|
|Photoflex (800) 486-2674||www.photoflex.com|
|Quantum Instruments (516) 222-6000||www.qtm.com|
|Sigma (800) 896-6858||www.sigmaphoto.com|
|Sunpak (ToCAD America) (973) 428-9800||www.tocad.com|
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