If you're looking for a lens for your Nikon camera, you can choose from various types of lenses. The Nikon F-mount is made for SLR cameras. The F-mount is divided into DX and FX. The Nikon DX mount is for cameras with an APS-C sensor and the Nikon FX mount is for cameras with a full frame sensor. In addition, Nikon has the Z mount for Nikon system cameras. The Z mount is also divided into DX and FX, with DX again being the APS-C sensor and FX the full frame sensor. In addition to Nikon lenses, lenses from brands such as Tamron and Sigma also fit Nikon cameras. You base your choice on the type of lens you need, the maximum aperture, and the lens series.