Basic Photography, 7th Edition

10

Exposure measurement

Strictly speaking, ‘giving the right exposure’ means making sure that your film receives the correct amount of image light (photons). In practice it is much more than this. Exposure can be used to give emphasis, by being correct for one chosen object in a scene, allowing other parts which are lighter or darker to be over- or underexposed. Exposure control is also the key to getting fine tonal qualities in your final pictures, whether prints or slides. And apart from its accuracy, the actual way you give exposure, via chosen permutations of lens aperture and shutter speed, has important side-effects on the image. As shown in earlier chapters, these strongly influence the appearance of things at different distances and the ...