Photographically we’re in an age of enlightenment. Whether you began your photographic journey with digital, the trip will go smoothly if you have a good understanding of basic exposure.
Image files captured with digital cameras have the same sensitivity to light as color slide film. If the exposure doesn’t let enough light reach the sensor, the image or part of it will be too dark. Conversely, too much light reaching the sensor results in a overexposed shot. Accurate exposure begins with correctly setting the lens aperture and shutter speed in proper relation to each other. You can set the exposure yourself, manually or let the camera do it for you. The manual method requires either a hand-held light meter or you can use the one built into the camera.
Believe it or not, there was a time when cameras did not have built in light meters. Photographers used a separate hand-held exposure meter or used a guesswork method relied on the data sheet packaged with each roll of film, providing basic exposure guidelines for taking photographs in bright sun, hazy sun, or cloudy—aka The Sunny 16 Rule. To take a photograph in bright sunlight, the camera’s aperture was set to f/16 and the shutter speed that came closest to the ISO number. For instance, if you were using ISO 125 film, the exposure would be 1/125th of a second at f/16. If you want to see how that works out, I wrote a post on this subject for Mirrorless Photo Tips.
When in camera metering was introduced it only worked in manual mode. There were no automatic, program, aperture or shutter preferred choices to select. Photographers still had to adjust the shutter speed and aperture themselves. For 90% of photographs made, the metering systems in digital cameras do a fantastic job.
If you agree that light is one of the key elements that separates a good photograph from a snapshot, then it’s still necessary to learn and understand proper exposure. The ability to tweak the exposure, even with today’s sophisticated cameras, can make or break your image quality and content. I’m always astounded at the number of people who don’t care about correct exposure, using the phrase, “I’ll just fix it in Photoshop”. There’s only partial truth to this statement when exposure is concerned. Photoshop has indeed become a favorite crutch for sloppy camera work, but be careful in the arena of proper exposure. A digital image that is too far over or underexposed cannot be completely saved with image manipulating software. Please re-read the last sentence.