测量范围：up to 6.00D

其他功能参数：同DTP 642

DTP 644
High precision transmission densitometer with
built-in light source and a throat more than 20
cm. long for measurements on large films.
The lighted area around the reading aperture
makes film positioning easier.
Interchangeable measuring apertures (2.5
mm. and 1 mm.) complete DTP 642
characteristics.
Functions: transmission density up to 6.00D
and very accurate dot area measurements (0 -
100%).

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