Test your lens
Knowing which aperture settings work best for your setup can save you time and ensure great results
Often, the aperture setting we choose is limited by external factors. For example, you need a small aperture to boost depth of field and a wide one for fast shutter speeds. However, there are many occasions when depth of field isn’t really an issue – if you’re photographing flat surfaces face-on, for example. When your subject’s stationary you can try a wide range of speeds safely, especially if you use a tripod.
At such times, you’re free to think about which aperture setting gives the best results from the lens you’re using. However, this can vary between lenses, so this issue’s assignment is to find out the optimum aperture for each lens you own. Here’s what to do…
Find some paper with fine-printed type – try a phone 1 directory or newspaper. Make sure that it’s completely flat and set up the camera to photograph it exactly head-on. The slightest camera-shake will make the results meaningless, so use a tripod.
Frame the page so it fills the viewfinder. Use Aperture 2 Priority (A) mode and set the aperture to its widest setting. Focus and take a picture. Repeat, working through the available apertures at full-stop intervals (see page 79). Repeat again for each lens you own.
Load the images onto your computer and view them 3 at high magnification. Resolution and contrast should improve visibly for images taken with a medium aperture, and decline as you approach the lens’s minimum aperture. Make a note of the setting that gives the best results with your lens.