You Only Need Two Lenses (But Nobody Knows Which Two)

Nikon D2Xs and Tamron 35mm f/1.8 lens. That combination - cropped sensor camera and 35mm lens - gives the old fashioned field of view of a 50mm lens on a 135 film camera. If you bought a camera, you got a 50mm lens with it. You could add more lenses, but many photographers never did. You can do a lot with a standard 50mm lens.

Received wisdom gives that the most useful alternative to a 50mm lens is a 35mm, which is a mild wide-angle (in olden days it was the only available wide-angle for a long time). According to one far Eastern expert*, a 50mm gives a lower yield of usable shots than a 35mm lens, but a higher yield of great shots.

A 50mm lens usually beats a 35mm lens on image quality, but possibly not by much. A 50mm lens will usually be faster by a stop or so. A 50mm lens is great value for money, providing good quality at low cost. However, a 35mm lens can do pretty much everything a 50mm lens can do and a bit extra, such as setting the subject in context; providing greater depth-of-field; being able to focus closer. Extending your options from a 50mm lens might involve adding a wide-angle and a telephoto. Extending your options from a 35mm lens probably involves adding only one extra lens, such as an 85mm or a 105mm.

Apparently, you do not need a 35mm as well as a 50mm (so it is claimed). A 50mm can replace a 35mm simply by means of the photographer taking one step backward. This supposes there is sufficient space. Deaths caused by falling off clifftops are highest amongst photographers.

It therefore follows that if you only have a 35mm, you can get the field of view of a 50mm by simply taking one step forward (again supposing you have space and/or there is no objection to the subject's personal space being invaded).

The general wisdom regarding being equipped with prime lenses is to go in steps which double; hence 24mm and 50mm; or 35mm and 85mm are possible foundations of a two-lens kit.

* Don't ask me who.