35mm equivalent Lens
Understanding digital camera focal lengths
Most people are familiar with focal lengths of 35mm camera lenses. Digital camera manufacturers describe focal lengths in terms of the lens length on a 35mm camera that will produce a similar area of view.
Focal length on one 35mm camera is the same for all others because the size of the film each uses is the same. Digital cameras, however, have different focal lengths because the size of their image sensors vary from one camera to another. Expressing focal lengths in terms of 35mm equivalent makes it easier for individuals to understand so they can compare digital camera lenses.
For example, here are the focal lengths for the Nikon 5400 digital camera and the 35mm equivalent:
| Lens | Nikon 5400 | 35mm |
| Normal * | 14.5mm | 50mm |
| Wide angle | 5.8mm | 28mm |
| Telephoto | 24mm | 116mm |
Zoom lengths are not all equal
It's important to realize that a 3x optical zoom on one digital camera may not give the same magnification as another with a 3x zoom. The Nikon 5400 has a 4x zoom, which when fully zoomed has a 116mm equivalent focal length. But Nikon 5200, which has a 3x zoom, has a 115mm equivalent focal length. Not much difference yet one is a 3x digicam and the other is 4x.
When buying a digital camera, it's important to ask the 35mm equivalent if looking for a specific focal length.
