Sometimes it's more of a judgement call
September 22, 2008
Even with today's sophisticated cameras, the ability to tweak the exposure at the moment of capture--and recognizing what tweaks you need to apply--can make or break your image's quality and content.
The Photoshop crutch
I'm always surprised at the number of people who don't care about correct exposure, using the already worn-out phrase, "I'll just fix it later in Photoshop." Where exposure is concerned, there's only a partial truth to that statement. For some photographers Adobe Photoshop and its sibling, Photoshop Elements, has become a crutch for sloppy camera work. You still need to be careful about proper exposure.
A digital image that is too over- or underexposed cannot be completely saved with image manipulating software.
Please re-read the above sentence.
While shooting with your digital SLR, you should make minor adjustments even to the automatic exposure settings, including the different metering patterns available in the camera. You might even have to pull out a hand-held meter from time to time.
Get it right the first time: This unretouched digital image of a Dodge Hemi-powered drag racer was made on the floor of the Las Vegas Convention Center. The hand-held exposure was 1/40th sec at f/4 at ISO 800, hence the shallow depth-of-field. ©2006 Joe Farace
What's is the "correct" exposure? That depends!
If "correct" exposure is a combination of shutter speed, aperture, and ISO setting that produces a pleasing result, who gets to make that determination? You do! There is no one right way to accomplish perfect exposure, although seminar and workshop speakers may disagree, arguing that only their way is the one, true perfect road. I disagree.
There is no "my way or the highway" in photography; you get to choose the way that works for you. Even a road less traveled is OK if it produces the results you want. If it doesn't produce acceptable exposures then its time to look at some alternatives and fine-tune them to your favored subject matter and preferred way of working.
Sometimes you will see the term exposure value (EV). This denotes all of the combinations of shutter speed and aperture that produce the same exposure. EV originated in Germany during the 1950s and persists to this day with purists who are more comfortable with it than the vernacular "stop."
"Light," as a wise photographer once told me, "may just be light" but you'll need to measure the amount to get the accurate or correct (for the mood) exposure. If the exposure doesn't allow 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 blown out or overexposed shot. Since accurate exposure begins by correctly setting the lens aperture and shutter speed in relation to each other, you can set the proper exposure yourself manually or let the camera do it for you.
The manual method requires either a separate hand-held light meter or you can use the one that's built in by setting the camera manual mode. For 90% of photographs you'll make, the metering systems inside digital cameras do a fantastic job in producing correct exposure.
Joe Farace is co-author of "Better Digital Available Light Photography" along with Pulitzer Prize winning photographer Barry Staver. It was published by Focal Press and is available in all the best bookstores, including Barnes & Noble and Amazon.com.