Unlike negative films, where exposure is keyed to the shadows and quite a lot of over-exposure is tolerable, the exposure for slides and digital sensors is keyed to the highlights: any but the slightest over-exposure will result in 'blown' (white) highlights.
With 'average' subjects, this does not matter, but if the brightness range is greater than 'average' you have to be sure that you are sacrificing the shadows and not the highlights. With unusually reflective subjects such as snow scenes or white marble statues you have to be careful to avoid under-exposure, and if the brightness range is very small there is again a risk of under-exposure.
As well as showing you how to use the optimum method (incident light metering) this module also explains how to modify conventional meter readings on the basis of experience and even how to use a spot meter to read the brightest white in which you want texture and detail.
Illustration from 'Exposure for Slides and Digital'
There are 13 pages containing approximately 4500 words and 19 different pictures, though two are equipment shots. There are also two comparison shots, making a total of 21 pictures.
Free modules you may also find of interest include the following:
ISO film speeds
Subject brightness range
18 per cent grey cards
Among the chargeable modules you may also be interested to read:
Exposing negative films
Obviously, the most useful of our books is likely to be Perfect Exposure.
Link to full module
Go to the unillustrated list of modules (in either alphabetical or date order)
or go to the illustrated list of modules
or go to the home page
© 2005 Roger W. Hicks