In this age of smartphones and tablets, quality photographs are much easier to capture, but there are limitations. Unlike digital single lens reflex cameras (DSLR), these mobile devices do not have interchangeable lenses. They have limited control over settings, a small CMOS image sensor and a small on-board flash. With DSLR, the lenses are made with extremely high quality glass, which maximizes sharpness and minimizes distortion. Lenses come in many different focal lengths from extreme wide-angle to telephoto; the lenses can be swapped quickly in situations where a certain focal length is needed. Another important aspect is the ability to change the f-stop. The ability to control the f-stop allows one to control depth of field, sharpness of backgrounds and other effects such as turning running water into angel hair. A photographer should have at least three lenses: wide-angle, normal and telephoto. With these three different focal lengths, one can cover almost all situations encountered.
Photographers like to control all aspects of the camera—ISO, white balance, shutter speed, focusing options, metering options, image quality, and many other settings. All this control leads to capturing the best possible photograph in any given situation. Mobile devices are programmed to capture images based on the metering of the light and zoom factor. DSLRs have the same capabilities when using shutter priority, aperture priority and program setting. Although not a setting, DSLRs can be mounted on a tripod or monopod. A tripod aids in capturing low-light images in a studio setting where repeatability is needed and in location shooting.
Sensor size and quality are the most important aspects of any device. With DSLRs, sensors are usually two sizes: APS-C and Full Frame. An APS-C measures 23.10 x 15.40mm and Full Frame is just that, 36 x 23.90mm. An iPhone 6 Plus measures just 4.89 x 3.67mm. That is quite a difference. The effective pixels are close, but because mobile devices have such small sensors, this means a wider-angle lens is needed to capture the image. That is why “selfies” are so easy with phones. The other difference is quality of the sensor. With DSLRs, the sensor is optimized for sharpness, color fidelity and dynamic range (the range of light from dim to bright).
Flash options are better with DSLRs. They have on-board flash which has higher light output and can be controlled. External flash units also can be used, such as studio flash units or flash units that can either sit atop the camera or be mounted on a bracket attached to the camera. Mobile devices have small flashes and lower light output, limiting their use to distances under 10 feet. DSLRs can also change the time the flash fires. The default setting is front curtain sync and fires when the shutter opens. Other options include red-eye reduction and rear-curtain sync (fires just before shutter closes).
Mobile devices are progressing in image quality, but their size limits them. For the best possible photograph, a DSLR is still the best choice for quality photography. My next article will address the challenges of shooting on location.