groping in the dark

Drawing the Curtain

You know when you change film, how you can see a venetian-blind-like section right in the middle of the inside of your camera? Don't touch it! That's the shutter curtain. Seriously, don't touch it! Shutters are very sensitive and expensive to replace.

When you take a picture and you press the shutter release (aka, "the button"), that curtain will open and close, briefly exposing the film to the light coming in through the aperture of your lens. The speed with which the shutter opens and closes is another of the factors determining your film exposure. The slower the speed, the longer the shutter stays open and the more light that can hit the film.

Once again, the correlation between what you would expect and what you camera tells you is backwards. In this case, when your camera tells you that the shutter speed is 15, that means the curtain is actually open longer than a shutter speed of, say, 250. The reason for this is that the camera doesn't bother to give you the time in fractions (which is what is being measured here), but just shows you the denominator. In this case, 1/15 of a second is longer (more light) than 1/250.

Depending on the age or sophistication of your camera, you should have a pretty wide range of shutter speed options. When my camera's shutter is open for a full second or longer, is is displayed with apostrophes (as in 2' = 2 seconds). Then there is the setting called "bulb". This means that as long as I hold down the shutter release, the shutter will remain open. This is what photographers use for those stars or taillights leave a trail of light through the shot. If you had a strobe light, you could expose several still images of a moving object on one frame as in the Harold Edgerton photo of the golf swing.

Unless I am shooting something in motion and I'm worried about problems with blurring, I usually don't pay much attention to the shutter speed. Instead, I worry more about the aperture and let the camera decide what my shutter speed should be. For me, this works fine, as long as there is enough available light with to for the shutter speed to be at least as fast as 1/30 of a second. Any slower than this and I get blurry shots from camera jiggle. If I have my elbow propped on a table, or I'm leaning against a wall, I can sometimes get away with 1/15 or even 1/8, but only when I'm feeling brave/stupid.

If I need the shot and I can't get enough available light otherwise, I'll use the flash. But really, the flash is boring. You get the same lighting in every shot which isn't all that flattering anyway, so I try my best not to use it.