Working Distance

The distance between the subject and the front end of the lens is referred to as the working distance. A larger working distance will make lighting and composition easier. Another commonly seen term is focusing distance, which referrs to the distance when the lens is focused at a particular subject. Normally, the focusing distance is slightly larger than the working distance because working distance is measured from the front end of the lens.

As we wll know that a shorter focal length yields a shorter working/focusing distance, hence a higher magnification. Virtually all consumer digital cameras use minimum focusing distance as the criterion for measuring macro capability. The following table shows some data. These cameras use different focal lengthes for macro shooting. Some of them use the wide angle end, while some use the middle focal range. Without knowing the focal length being used, the minimum focus distance tells little about the macro capability of the lens and camera.

Moreover, it is very important to know that lenses with different focal lengthes can have the same magnification at different focusing distances. The table below shows various 1:1 life-size capable SLR lenses for Nikon SLR/DSLR bodies and their minimum focusing distances. It clearly showss that a lens with longer focal length has a larger minimum focusing distancce, even though all of the listed lenses have the same magnification. Consequently, the minimum focusing distance does not provide much information about the macro capability of a lens/camera.