FOR CHOOSING A TELEPHOTO LENS

• Telephoto lenses can be big and heavy, so use a tripod or monopod

• If you’re using a DX-format Nikon, the effective focal length is multiplied by 1.5

• Optical stabilisation is a massive help if you are shoot ing handheld

• A wide available aperture is useful when you’re shoot ing in low ligh t condi t ions