"The flash didn't go off" has been shorthand for photographic failure for more than 100 years, but the conventional wisdom on lighting is now being challenged by advances in camera technology. The quickest, simplest, cheapest way to take more professional-looking pictures of your friends and family is to stop using your digital camera's built-in flash.
Take a look at these photos:
The above are pictures of my 18-month-old son taken in nearly identical situations. But the pictures on the right are more attractive to most people than those on the left. The ones on the left were shot with the camera's built-in flash; the ones on the right were shot without a flash. There are some technical reasons why the flashless photos look better, but you don't need to be a professional to shoot this kind of photo. With the right camera and the press of a few buttons, you can be taking better photos of your family in no time.
There are two main differences between built-in flash and no-flash pictures. The first is the fuzziness in the background of the no-flash photos, which removes distraction and places attention on the human subject. (It also tends to make the everyday mess of kitchens and living rooms disappear, which is particularly advantageous for home photographers who don't have time to design—or clean up—their backgrounds.) This fuzzy look is much sought-after by professionals, who will sometimes spend quite a lot of money to get it. Here are two no-flash photos that feature this effect:
The second, more important difference is that people often just look more attractive in available light than they do lit by a camera's built-in flash. Photography is often called "the language of light," but shooting with an on-camera flash, almost regardless of what camera you're using, means you're just repeating the same monosyllable. The location and size of an on-camera flash makes people less attractive by producing glare and unattractive shadows and by frequently being off-color. The endless variety in available light offers the opportunity for something much richer.
In order to comprehend how to take advantage of these differences, a bit of technical understanding is useful. There are three settings that affect how light is captured by the camera's sensor: shutter speed, aperture width, and ISO. Shutter speed determines the length of time in which light will be exposed to the sensor. (The sensor takes on the role of film in digital cameras.) The width of the aperture controls the amount of light that gets through to the sensor. And the ISO programs the sensor's sensitivity to the light that hits it. Each of these three settings can be adjusted to allow more or less light into the final image, and each adds its own separate element to the picture.
The most important factor in making a person look attractive is capturing them sharply, without motion blur. In a no-flash photo, this requires a high shutter speed. But when you increase the shutter speed, exposing the sensor to light for less time, the other two settings need to compensate, or your photos will be too dark.
If you set your aperture to be very wide, you can compensate for the loss of light your fast shutter speed created, but even at the widest apertures, film and earlier digital technology couldn't reach the ISO levels necessary to produce a good picture—most were at best ISO 200, and even the ISO 400 or 800 that sports photographers used still needed more light than the average room has. It's only recently that the technology behind ISO progressed to the point at which you can take a decent picture with the limited amount of light indoors without adding light from a flash. Cameras now can reach levels of ISO 1600 or 3200 at an acceptable level of quality. Just a few years ago, this was far beyond any camera's capability, no matter how expensive. In the past year, this capability has reached consumer-level cameras.
The ability to capture light this well and this quickly gets you a sharp subject using only available light. The part that will be blurry is the background—a side-effect of having a wide aperture. The result is a look that professionals often pursue in portrait photography, of a short "depth of focus." These photos show how this depth of focus changes at different apertures, and will at times create what photographers call a "bokeh" effect, in which distracting background elements come to look like jewels of light decorating your subject.
Camera manufacturers are beginning to see a marketing angle in this low-light shooting trend (a trend that led Gizmodo to declare recently that "ISO is the New Megapixel"). I tested several models that manufacturers tout for their low-light performance, and I was pleased to see that most of them listed their ISO and/or aperture capabilities right on the box. Alas, we're now seeing manufacturers push out cameras with the technical ability to capture photos at high ISO settings, but with too much degradation in the quality of the final product, so consumers should be wary. But some cameras really can perform capably at very high ISOs.
The simplest and most reliable way to shoot good low-light pictures is on a camera that has an "Aperture Priority" mode. This lets you set the aperture as wide as the lens can go, and also switch the ISO higher or lower if you want, and then the camera will get the best shutter speed it can with those settings. And if you've got more light than you need, you can close your aperture a bit to increase your depth of focus, or decrease your ISO to produce pictures with less noise.