The exposure compensation dial. What's it for, exactly? And who on earth uses this completely useless knob that's taking up precious space on top of so many camera bodies?
These were my questions as I stared at the range of Fujis and Sonys in the camera store the other day. In the 15 years that I've been shooting on an SLR and a DSLR, I've never used it, and can't imagine a situation where I would ever need it.
I'm not a manual purist but I always like to know exactly what my camera is doing. I base my exposure decisions first on the camera's recommended exposure, and then on the histogram once I've fired off a test shot (this will probably change if and when I shift to mirrorless as the in-view histogram and accurate EVF will reduce the amount of chimping). Given that I spend a lot of time shooting upwards and incorporating a lot of sky, I often have to ignore my camera's suggested exposure and let more light into my lens, trying to achieve detail in the shadows while retaining a slither of information from the highlights so that I can squeeze a bit of detail into the sky when editing. This often means shooting one or two stops above what my camera says is correct and, despite this, still creating an image that is slightly underexposed (with a histogram in which the mountains are mostly on the left) that gives me more flexibility in postproduction.
For those of you unfamiliar with exposure compensation, here's a quick explanation. Cameras detect the amount of light of any scene and make a judgment on what will make the best exposure. In fully automatic mode, this is used to decide the shutter speed, aperture, and ISO, and even in manual mode, many cameras will give an indication of whether your settings will give an exposure that it regards as under, over, or perfectly exposed. However, despite the technological advances of the last couple of decades, cameras are still very easily confused by surprisingly simple things like snow, large amounts of sky, or darkness.
The exposure compensation dial gives you the opportunity to adjust the camera's assumptions of what is the right amount of light. For example, shooting a snowy scene can mean that there's a lot of light entering the lens, and the camera's recommended exposure can often try to make a more balanced image, letting in less light than we might want, and making snow appear dull and gray rather than bright and white.
My approach might be to shoot a test shot in auto (often "P" on a camera's mode dial), check the histogram, switch to manual mode, and make adjustments from there. Alternatively, with the exposure compensation function, you can stay in auto mode but can tell the camera to allow more light in, often by increments of one-third of a stop. On a Nikon or a Canon, this is adjusted by holding a button marked "+/-" and turning one of the dials. On a Fuji or a Sony, this can be achieved slightly more efficiently by using the huge dedicated dial found on top of the camera.
This dial is a complete waste of space. For anyone learning photography and trying to get their head around the exposure triangle, exposure compensation is an unnecessary distraction, complicating an already complex set of variables and their confusing number systems.
When I'm photographing, I always want to make sure that my camera isn't creating a setting that's going to disrupt my intentions for a shot. For example, for my action photography, I want to be sure that my camera isn't choosing a shutter speed that's too low, an aperture that's too wide, or, occasionally, an ISO that's too grainy.
Furthermore, I know that the camera's recommended exposure is just a vague clue as to what the histogram is going to tell me, and it's through the histogram that I'm going to make a judgment on the correct exposure.
Given how useless the exposure compensation function is, why do some manufacturers insist on having such a massive dial dedicated to it? Maybe I was missing some crucial trick that could improve my photography. Intrigued, I asked my Fstoppers colleagues if they ever used exposure compensation. The answers were quite surprising.
From my random, completely unscientific straw poll of 13 photographers, 6 said that they don't use it, with most of those never once using it during their time as photographers. "Exposure who?" asked Tihomir Lazarov, explaining that, other than exposing manually, he rarely uses any of the additional functionality of his camera beyond formatting a memory card. Nicole York agreed. The thought of a dedicated dial seemed as ludicrous to them as it was to me.
The remaining seven photographers had completely different thoughts. Wasim Ahmad, Alex Cooke, and Lee Morris use exposure compensation extensively. Ahmad finds that his camera's decision making often creates shots that are over-exposed, and Cooke likes to make sure that he's not blowing highlights when shooting baseball with his ISO set to auto. As Alex Armitage pointed out, it's always better to recover shadows in post-production than blow highlights when shooting, so in high contrast situations, he tweaks his exposure compensation to -1.
Suddenly this setting was beginning to make a little more sense, but a huge, dedicated dial still felt like overkill. And then this from Jason Vinson: "I use it so much I'd never consider a camera that didn't have a dedicated dial for it. If I'm not focusing, my thumb is on the dial." And as Morris observed, "With flash photography, it’s the quickest way to dial an exposure without going full manual."
So here's my second straw poll: our readers. Do you use it? And if you use it, do you need a giant dial dedicated to it, or is that knob a stylized hangover that's wasting precious space on an already crowded camera body? Please vote and, as usual, let us know your thoughts in the comments.