4. ISO Settings

ISO settings indicate the sensitivity of a DSLR camera. Most DSLRs offer 100 to 1600 ISO settings. The highest end cameras feature settings from 50 to 3200 or even 6400 ISO. Support for higher ISO settings lets you take pictures in darker environments using smaller f-stops or faster shutter speeds. These options allow for sharper images because of the greater depth of field that comes with smaller f-stops and the action freezing result of using faster shutter speeds.

But don’t let ISO settings drive your DSLR buying decision too strongly. In most lower cost, entry level DSLRs higher ISO settings result in moderately to really noisy images. That’s why some of these cameras actually require that you take extra steps to enable higher ISO settings, for example by choosing the option using the camera’s menu system. Modern pro DSLRs generally can produce useful images at even their highest ISO settings.

Exposure Metering

DSLR metering has been honed to a science, especially on professional digital cameras from Canon and Nikon. On these the number of segments of the image used to calculate exposure has been optimized, providing spot, center weighted and average exposure capability. Even less professionally oriented DSLRs from other vendors do a very good job of exposing images.

Shutter Speeds

Even the least expensive of the current crop of DSLRs provides shutter speeds ranging from 30 to 1/4000 of a second. Pro cameras deliver speeds from 30 to 1/8000 of a second and are more accurate than entry level shutters. If you expect to use your camera a lot, consider a pro DSLR; shutters are better made and have a higher predicted life.

Built-In Flash

Some photographers believe that a pro DSLR shouldn’t have a built-in flash. So, most higher-end DSLRs don’t and you need to carry a relatively heavy flash attachment for those situations where ambient light just won’t cut it. It’s my guess that even the most anti-built-in flash photographer has had those moments when she or he wished for built-in flash, because, in spite of great low-noise ISO sensitivity, low shutter speeds and large f-stop lenses, an image was lost because of inadequate light.

Manual White Balance And Exposure

Almost all DSLRs offer manual control over white balance and exposure. These allow you to override the automatic or preset settings offered by your camera. Manual white balance allows you to more precisely set white balance for the type of lighting you’re working in. Manual exposure settings let you control the quality of your images in various ways. You can set the lens aperture and let the camera set shutter speed (aperture priority or AP). This allows you to control depth of field or to take advantage the lens’s best f-stop settings. You can set the shutter speed and let the camera set the aperture (shutter priority or SP). This allows for stop action and control of camera shake. Or you can set both f-stop and shutter speed (full manual). So you can control exposure to achieve a particular artistic effect.

Memory Cards

You’ll want to check out the memory cards supported by DSLRs you’re considering. Compact Flash cards typically have greater capacity than other cards. However, the new Secure Digital High Capacity (SDHC) cards now or soon will surpass CF cards in capacity. Some cameras allow you to use two different kinds of cards either simultaneously or by switching from one to the other. xD cards, while small and allowing smaller camera bodies, still are available only in lower capacities.