Practical Artistry: Light & Exposure for Digital Photographers

57

Working with Aperture

I took this photo using an older fixed-lens digital camera with a quite small

sensor. I used the camera’s manual exposure controls to stop the lens as far

down as it would go (the smallest aperture was f/8).

Due to the small sensor size, the f/8 setting gave a remarkable amount of

depth of field for a macro photo (more like you’d expect in the f/16 to f/22

range when using a moderate telephoto on a dSLR with a larger sensor).

Canon Powershot G3 fixed-lens camera, sensor with a crop factor of approxi-

mately 4.5X, 28.8mm (140mm in 35mm equivalent terms), macro mode, 4/5 of

a second at f/8 and ISO 50, tripod mounted.

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58 Working with Aperture

With wireless flash units seated on a ring at the end of my macro telephoto lens, both camera settings

and the amount of light the strobes emitted were controlled from my camera. I knew that at the 1/60

of second flash synch speed, the motion of the bee on the flower would be stopped by the effective

exposure time, namely the duration of the flash—a lot shorter, of course, than 1/60 of a second.

(Depending on the flash unit and its power source, the flash duration can range between 1/10,000 of

a second and 1/250 of a second.)

Using the flash, the exposure time was determined by the flash, leaving aperture as the creative ...