The main function of the caption is to enhance the photograph, adding detail such as names, locations and other pertinent information. Captions are also used to tie the photography to the wider text in the book and to reinforce major points brought out elsewhere.
There are five questions that need to be answered, although not on every occasion and depend on the type of publication.
If the photograph accompanies a news story it is essential to write the caption for readers who will not read the main text, in which case as much of the WWWWWH should be covered. The words should not be wasted and phrases such as "is pictured" or "is shown" avoided as the photograph already
serves that purpose.
The version above is suitable for an outdoor magazine and is aimed at walkers and ramblers. It fixes where the photograph was taken, and takes account of an international readership then details the specific location. The reader may be familiar with the location, in which case they will recall their own experiences and there will be those who are making plans to visit the area, in which case the caption and image acts as a marketing tool.
The version above makes no reference to its location and the caption deals specifically with image composition, the colour of the light and the diagonal line of the wall. It is likely that the image would be to illustrate are sizable amount of instructional text associated with an article on landscape photography and the various composition tools that can be employed.
Photojournalism - Photography with a Purpose, Robert L Kerns, Prentice Hall International.