Crop factor is the ratio of the camera sensor size to what the lens can see. DSLRA digital single-lens reflex camera (digital SLR or DSLR) is a digital camera that combines the optics and the mechanisms of a single-lens reflex (SLR) camera with a digital imaging sensor. The reflex design scheme is the primary difference between a DSLR and other digital cameras. In the reflex design, light travels through the lens and then to a mirror that alternates to send the image to either the viewfinder or the image sensor. The viewfinder of a DSLR presents an image that will not differ substantially from what is captured by the camera's sensor but presents it as a direct optical view through the lens, rather than being captured by the camera's image sensor and displayed by a digital screen. DSLR is often (wrongly) used to describe cameras that are Micro Four Thirds or Bridge Camera - just because they look similar. This can bee seen when cameras are offered for sale. [rdp-wiki-embed url="http://camera-wiki.org/wiki/DSLR" toc_show='0′ edit_show='0′ infobox_show='1′] More cameras often have multiple sensors of varying sizes to control for distortions that come from crop factor. It describes the difference between your camera’s sensor size and a traditional 35mm film frame. It’s mainly used as a way of comparing lens focal lengths when fitted to different cameras. A cropped sensor captures less of the projected image. The narrower angle of view gives the impression of using a longer focal lengthThe optical distance in millimetres between a camera lens and the film (or sensor on a digital camera). It determines the height and width of the scene being captured, known as the field of view. More. For micro four thirds this is two times. For example, a 50mm for a 35mm camera is equivelent to a 25mm micro four thirds lens.