P-series
The Sinar P, introduced in 1970, had asymmetric tilts and swings, as opposed to the traditional center or base tilts. This permitted rapid and precise settings without losing sharpness on the axis.
The P series also introduced features such as self-arresting rack and pinion gearing and a precision-engineered quick format change system that allows the photographer to switch between 4x5/5x7/8x10 formats quickly without having to fully disassemble the rear standard. This was accomplished by using a common rear standard bearer and unlocking a single knob to switch among the various format frames. Another new feature implemented in the P series was the Sinar system of calculating swings and tilts as well as the Sinar depth of field calculator. A key feature of the Sinar P system, particularly in the domain of scientific and industrial photography, is the precise machine tolerances that are part of the fittings and movements.
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