ABSTRACT
Establishing the Correct Exposure If you are using Speedlights, it’s important to determine the correct position relative to the subject. You want the background to be white, but not entirely overexposed; half a stop is adequate since a certain amount of light travels through the Perspex to the subject making it appear to glow. e closer the background is, the greater the radiance. With experience, you become more familiar with the distance and how far it needs to be to achieve the correct exposure. Once in position, make a series of test exposures with the background ash only and make the necessary adjustments to the ash output or via the ISO or aperture. e correct value is obtained when the highlight warning in your camera shows the background ashing but not the subject. e histogram reading will naturally show a bias to the middle and right side of the screen with virtually no values registered on the left side. With pale subjects, you need to keep the background further back to achieve the desired result otherwise nely featured or translucent parts of your subject may become overexposed and blend with the background. With darker subjects, it’s the opposite, the background needs to be closer. When you are satis ed that the background exposure is correct, you can perform a similar procedure with the front ash. Better results are obtained if you use diusion; this can be accomplished by using a softbox attached to your ash unit or a large opaque envelope stiener which produces a similar result. You want to place the diuser relatively close to the subject and vary the position of the ashgun until the correct exposure is attained. You need to run some test exposures to make sure the subject is not overexposed.
