Exposure: Get It Right

Exposure - Dark or Light, Get It Right
Good exposure is the second element I feel is a necessity for a quality image, but before we delve into what constitutes good and how do we get there, let's talk about types of lighting.

If you're shooting indoors, unless the area you're in has extremely bright lighting, you're probably going to be depending on your flash for virtually all your shots. Once you manage to sneak your camera in unobserved in the hopes of striking candid portrait gold, I guarantee your cover gets blown with that first blinding flash. After that, chances are at least some folks are keeping one eye on the guy with the camera and your candid opportunities may dry up a bit.

Two film scans follow: in the one on the left, the boys were into their adult beverages and didn't catch on I was aiming an SLR and flash their way until their world lit up. In the second Al saw the shot coming and instinctively aped for the camera with Mrs. Al. I still like the shot, but it turned out like it did because he staged his part (she was caught by surprise), reacting to the presence of a camera.

Unfortunately, compacts pretty much universally don't have the high ISO noise performance to allow you to ramp up ISO and get shutter speeds fast enough to hand hold indoors without flash unless you're willing to pay a pretty severe image quality penalty due to noise. Shooting at the wide angle end of the zoom is the best way to try low light without flash as the camera's maximum aperture is available there, and the wide angle is a bit more forgiving of camera shake at slow shutter speeds. The other side of this coin is that at wide angle you'll need to be right up on the subject for head or head/shoulder shots, and the perspective with a wide angle may not be what you're looking for. We'll discuss some ideas on lens length later in this article.

Where things get interesting is shooting outdoors, making use of the light you've got and recognizing other lightning options that may exist. Direct sunlight is easy to recognize and difficult to make look good for portraits, particularly during the hours when the sun is overhead. Deep shadows under eyes, noses and chins from direct sun look terrible, so whenever possible, see if you can shoot from an angle where your subject's face is backlit. You're trying to capture the image from a point where the face is shaded and not lit directly by the sun. Here's a film shot (left) and a digital (right) with the model backlit in each case - not candid, but good examples of shading the face from direct light.

Backlight is by no means perfect - if you've got a light background highlights are going to get lost because you're going for an exposure that looks pleasing for the darker shaded portions of the face, and the lighter regions get overexposed as a result. But the good news is that more and more compact digitals are coming with settings that allow you to capture images which expand the apparent dynamic range (the ability to record detail in highlights and shadow) of your camera. Some models even have a "backlit" mode. If your camera has these type of features give them a try with backlight to see how they do.

Another option outdoors is to look for open shade - try to find a spot where your subject is in an outside shaded area, such as the shadow of a tree, wall or anything that casts enough shade to blanket your subject. Open shade has the advantage of often providing a fairly even light without the directional highlights of backlight - you may have many shooting angles compared to a backlit spot. Here's a pair of digital open shade shots.

Back when we all shot film, you had to be a bit careful about film choice for certain conditions. For example, folks shooting Ektachrome, a Kodak slide film, would find that shots in open shade could take on a bit of a blue cast. Fortunately, the auto white balance setting on most compact digitals does a pretty good job across a range of light, including backlight and open shade, so unless your subject is getting hit with reflected light from a colored source, color reproduction should be pretty good in most cases outdoors. Be wary of your white balance if you're shooting under incandescent light or your subject is getting some illumination from incandescent - most compact digitals shoot a bit warm in these conditions with auto white balance and switching to a tungsten or incandescent WB preset would be a likely cure for warm shots.

OK, you've found an angle to your subject that puts the face in a shaded configuration. What to do about exposure?

Most compact digitals use a multi-point metering system as their default to calculate exposure - the camera reads light levels at various spots across the image frame and uses these to come up with an exposure level. Depending on the camera brand, this method may be described as "matrix", "evaluative" or some other descriptive term. Because these type systems read light across the whole frame, they are metering areas that are not our principal interest - the face - and the overall exposure might cause the face to be rendered somewhat darker than we would like. Exposure compensation is an option, but it may take a few shots for you to dial in the right setting for that scene, and when you point the camera in another direction the lighting levels there may require different or no compensation.

Here's another option to try: virtually every camera also offers center-weighted or spot metering methods, and in most cases both. Center-weighted metering takes readings from various points on the frame but assigns a higher level of importance to the readings from the center (on the theory that this is the most important part of the image). Spot takes a reading from a relatively small area and uses that to calculate exposure. Either method will likely produce better results for a backlit subject than the matrix method if you position them on the face or shaded portion of the subject. Since they're calculating exposure largely from the area of greatest importance to the image rather than a wider field that may contain bright background highlights, they'll tend to get you closer to a pleasing exposure, assuming the subject is of average complexion.

Folks with very light or dark complexions may require some exposure compensation even with these methods, and you need to be particularly careful when using spot that the location you meter on is representative of the general illumination in the area of interest, and not an isolated light or dark patch.

The big advantage we have with digital over film is we can see the results immediately and take steps to fix images coming out of the camera that aren't what we want. We also don't have to depend on a darkroom and various printing techniques to change the way images look once on film - a basic software program like Photoshop Elements and a computer allow us to manipulate digital images after they come out of the camera.

So, what's a good exposure? I would argue it's one where the important parts of the image are exposed in a pleasing manner. Back in the film days it was not unusual for folks shooting portraits of women to overexpose by a third or half stop in order to lighten the skin tones a bit, which sometimes seemed to help hide minor blemishes and smooth features. Digital cameras make it easy - practically every one offers exposure compensation. If you're shooting women and expect to be doing a lot of head or head/shoulder shots, try some with +.3 or +.5 EV compensation and see if you like those results better. Here's a backlit digital shot and the same image with +.5 EV exposure compensation.

Base

Base +.5

Don't go overboard sharpening with close ups of women. Digital shots need to be sharpened somewhat and many cameras offer additional settings beyond the defaults that come in the camera, but too much sharpening may bring unwanted attention to skin imperfections that we're trying to downplay (in most cases) with a woman.

As you might imagine, things tend to go the other way with men. Normal exposure or a bit of underexposure may impart a more masculine, rugged look to an image, and if your sharpening accentuates skin flaws it's more acceptable than with a woman.