SLR digital cameras

Nikon D300 (body only)

SLR cameras are the cameras with detachable lenses that professional photographers use. What does SLR really mean? Single Lens Reflex means that the same lens is used for viewing and taking pictures. In other words, you view the scene through the same lens that takes the picture. These types of cameras use a mirror positioned behind the camera lens to direct light toward the viewfinder when you're composing a photo. Light entering the lens is reflected by a mirror up into the viewfinder (eye-piece), allowing the photographer to see exactly what the final picture will look like. When you release the shutter, the mirror moves out of the way, letting light from the lens travel straight to the sensor and momentarily blacking out the viewfinder.

SLR's are much larger and heavier than point-and-shoot cameras and have better autofocus systems. Tele-zoom lenses, macro lenses, wide angle and fish eye are some of the lenses that may be added to most SLR cameras. They are faster at starting, focusing, taking pictures, taking multiple pictures; better at taking pictures under low lighting situations by using higher ISO speeds (no graininess); and offer more professional control over light and depth of field.

• 2007-02-08   Breaking the Myth of Megapixels   New York Times 
  • "The actual lesson, then, is this: 'For the nonprofessional, five or six megapixels is plenty, even if you intend to make poster-size prints.'"

• 2007-05-22   Single-lens reflex camera    
  • The single-lens reflex (SLR) is a type of camera that uses a movable mirror placed between the lens and the film to project the image seen through the lens to a matte focusing screen.