Density And Contrast Relations - Siemens MOBILETT XP Instructions For Use Manual

MOBILETT
SPR8-230.621.01.03.02
The Exposure Point System
The exposure point system allows to easily change the density or contrast on the
film. Therefore, the kV and mAs may appear to change in odd steps. Step data is
shown in chapter Technical Data
(→ Page 77)

Density and contrast relations

For example, pressing the kV+ button once (using whole exposure points), or
pressing the mAs+ button twice, will increase film density by 25%. If double
density is desired, press the kV+ button three times, or the mAs+ button six
times. Observe that changing the kV affects both the density and the contrast.
If an exposure yields accurate density but should be higher in contrast, it can
easily be adjusted. Pressing the kV- button once (using whole exposure points)
and the mAs+ button twice will yield the specific density and the desired
contrast.
If the kV is set to step in half exposure points, it will correspond to the mAs steps
(e.g. press kV+ button six times for double density).
The Exposure Point System
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