Gossen STARLITE 2 - Manual (Page 34)

34 Gossen Foto- und Lichtmesstechnik GmbH
Contrast and Ideal Exposure
The basic rules for ideal exposure specify that the
brightest and darkest parts of the image must show
adequate detail. Personal taste and creative artistic
intent may, of course, render these rules null and void.
Thus only general recommendations can be provided
regarding the subject of ideal exposure.
It’s important to consider the fact that the final product
(photo, print etc.) is only capable of processing a small
contrast range in comparison with the human eye.
With the STARLITE 2, you can determine lighting
contrast with the incident light measurement method
and object contrast with the object measurement
method. In both cases, contrast is shown at the analog
display.
It usually isn’t possible to determine correct exposure
for your motif by measuring the brightest and darkest
points. These should be either a medium gray within
the motif, or the mean value of the measurement
results for the brightest and darkest points. The mean
value is calculated automatically by the STARLITE 2.
If you make sure that object contrast is greater than
your workflow is capable of processing, you can
brighten up shadows, for example with a brightening
screen or a flash, and thus reduce object contrast.
When object contrast is taken into consideration by
means of mean value generation, the following rules
of thumb apply:
Negative Film
If two steps (exposure values) are not exceeded
between bright and dark areas which are important for
the image, each intermediate value could basically be
used as a setting value (the mean value is more
appropriate for more exacting demands). This
produces a usable picture in most cases.
Denser negatives result in reduced definition.
In the case of negative film, the lowest, but
nevertheless still printable density is important, and it’s
thus better to overexpose a bit rather than to
underexpose.
Digital Photography
– Color Transparency Film
In comparison with negative film, color transparency
film is capable of managing greater object contrast,
but its practically useful exposure latitude is
significantly smaller.
Measurement of object contrast is the basis for
deciding whether or not the motif can be reproduced
realistically. If the motif necessitates nothing further,
it’s advisable to measure against the lights.
In the case of color transparency film, the important
bright parts of the image are most significant. Keep
this in mind, and remember that it’s better to
underexpose a bit rather than to overexpose. In this
way, the colors appear more luminous and rich.