SLR is a shortened term for single lens reflex camera. These cameras are named this because of the fact that they have a mirror that is situated behind the camera’s lens. This mirror directs light towards the viewfinder when you construct a photo.
The mirror then swings out when you release the shutter button. This allows the light from the lens to travel straight to the sensor. This is in turn momentarily blacks out the viewfinder. In a digital SLR camera the viewfinder incorporates a pentaprism. The prism usually flips the image around so that you can see it right side up. It then bounces onto the focus screen for even easier viewing.
The main reason that SLRs dominate so much of the photographic field is because with one camera you can accommodate a huge range of focal lengths. With non-SLR type cameras you have to match angle views with the taking and the viewing lens. If you are interested in covering a wide range of focal lengths, this can become quite costly because it will require you to purchase rather expensive viewfinder mechanisms.
You can avoid such an issue altogether with an SLR type camera. This is because the taking and the viewing lens are both the same.
Different types of digital SLRs
Digital SLR-Fixed lens
These cameras do not have a removable lens and this limits their functionality. You are able to use LCDs for composing, and these cameras have a nonmoving semi-transparent mirror. This does bounce some light to the viewfinder.
Full system digital SLR-interchangeable lens
What sets these cameras apart is their ability to go from one lens to the next very easily. You can go from ultra-wide to super small very quickly just by removing a lens and replacing it with another one. Most all of the digital SLRs available today have interchangeable lenses.
These are interchangeable lens cameras but use the point and shoot philosophy. This camera also supports an interchangeable lens mount. Olympus/Panasonic was the first brand to produce a standard in this group of SLRs.
If you want a digital camera that can stand up to the diversities of the photographic world, then a digital SLR is your best option. There is nothing else like a digital SLR when it comes to superior photo quality. Several of the major manufacturers of digital SLRs offer more than forty different lens types each designed for specific purposes. Digital SLRs are the cameras of the future. Join the revolution today.