If you are shopping around for your first ever DSLR camera, then there is one factor that you might want to learn about and that is the “crop factor.” The reason that this feature is important is that it might give you a different lens performance than you expect. When it comes to compact digital cameras, what you see is that you get and if the compact camera comes with a 35mm equivalent lens, then you would get the same performance as a 35mm lens. However, this is not necessarily true in the case of DSLR cameras.
The sensors of most DSLR cameras is smaller than a 35mm film and a camera with 1.5, 1.6, or 2.0 crop factor will capture smaller area and “crop” the view. If you use a lens with 100mm focal length and the camera has a 1.5 crop factor, then the final, adjusted focal length would be 150mm. The photographers that are likely to take more indoor or landscape photos are the ones that should be typically concerned with the crop factor or at least take it into account when buying lenses for their DSLRs. However, if you take more wildlife, portrait, or macro shots, then you might not have to worry about this issue at all. One way to work around it though, is to purchase a DSLR that has a zero crop factor, or a full-frame DLSR. These cameras typically cost more and depending on your needs, purchasing one might not be justified at all.
Another fact that is good to know is that all camera manufacturers use a consistent crop factor for their cameras and therefore the number does not vary from one camera model to another within the same brand. The terms focal length multiplier and focal length conversion factor are often used instead of “crop factor” and the most common numbers are 1.5x, used by Nikon and Sony, 1.6x, used by Canon, and 2.0x, used by Olympus.