The fundamental look of our images is controlled by many factors: subject, composition, lighting, focal length, color. One element of our imaging that stands out as particularly important is exposure. Our images are made of light, so how much or how little light we show in them is at their heart.
I thought of this for two reasons. First, someone emailed me with an exposure question. Second, I happened across yet another raging debate on Photo.net this morning about “expose to the right,” a hot-button issue regarding exposure in the digital age.
Before we dive into exposure control, let me stridently assert this: exposure, like most factors in photography, is subjective. If anyone every tells you that your opinion about exposure is wrong, they’re wrong. We all have a unique perspective on imaging.
The email I received, however, was a fairly straightforward question from someone just learning about photography: “I think I have sufficient lighting but my pictures come out dark. Any suggestions?”
The answer is, thankfully, a reasonably easy one: learn how to use exposure compensation. Exposure compensation is the way we tell the camera to expose the sensor to more or less light. On many cameras, it is controlled by a button with a +/- on it. We push and hold the button and turn a dial (the main command dial on Nikons) left or right to change the amount of exposure compensation, usually by one third of an f/stop at a time. When you bought your camera, this value was set to 0.0. We can change it to values like +0.7 or -2.3, and so on. Plus makes the image brighter, while minus makes it darker.
Of note is that exposure compensation is usually disabled in “green box” auto mode or scene modes, so to use it, you need to be in one of three exposure modes, P=Program, A=Aperture Priority, or S=Shutter Priority (Canon cameras use Av and Tv for the last two). (See The PASM for more on these modes.) Also, note that exposure compensation has no effect in manual mode, because in manual mode, we pick all the settings.
I mentioned “expose to the right” earlier, so I should explain: there are those who believe, often very dogmatically, that the histogram (see the image of the display on the back of my camera; the histogram is that thing that looks like little mountain ranges) should be stacked to the right. “Expose to the right” is a worthless tome because it’s only effective some of the time, and treats us as robots who need rules to follow.
In my occupation, news, magazine and sports photography, human faces take priority over other shadows and highlights, so much of the time I try to expose so we can see who, not what.
This is a nice write-up on the subject. I’ve seen some that are very much more complicated (and therefore less helpful).
You did say that manual (“M”) doesn’t use exposure compensation. I’ll note that this is one reason I almost never use exposure compensation; the majority of my photos these days were made with M mode.
As for “expose to the right”, that reminds me of the phrase “correct exposure”, which is almost as meaningless in the way it’s normally used. Correct exposure is what you want it to be. (Depends on intended audience, of course.)
This image was drastically underexposed intentionally for effect, yet there are parts that overexposed. We make choices depending on what we want the outcome to be. 🙂
Thanks, Wil. I will also note that I once posted a photo (attached) on Photo.net asking if anyone had a Photoshop plug-in that would help reduce the blue haze in the distance. When I was unambiguously informed that the image was “horribly overexposed,” I took it, and my post, down.
Most photo.netters are know-it-all jackasses.
Wil and other commenters might take note that you can upload images to comments on any richardbarron.net site by using the dialog below the “Add your Reply” button.
Ha. I’ve seen very similar posts on Flickr’s forums answered by the same know-it-all jackasses.
You can tell who’s been burned by them in the past because they preface their posts with long explanatory paragraphs to head off the irrelevant criticisms (“I realize the sky is blown out; I exposed this way intentionally. Please don’t comment that the image is ‘overexposed’ when all I’m asking about is the blue haze. Thank you.”)