Compound portable microscope by Hensoldt, c. 1925
Inscriptions: Protami HENSOLDT WETZLAR 2092 (on top of metal cover)
HENSOLDT WETZLAR D.R.P. Protami Vergr.40 - 1200 (on focusing tube)
Dimensions: Weight: 1008 gr. (packed), 849 gr. (unpacked).
Height: 177 mm. (packed), 260 mm. (unpacked, tube fully extended),
Diameter: 71 mm (base)
The "Protami" (professionellen - taschenmikroskop) is the high end model of the Hensoldt "Tami family". The Protami was introduced in 1925, with production continuing until the beginning of World War II. Design improvements occurred between the 1920s and 1930s.
The Protami is constructed of brass with chrome and a japanned surface finish. Its saltshaker-like outer case is made of aluminum alloy finished in black-crinkled enamel. The inscription D.R.P. means "Deutsches Reichs Patent", i.e., German Reich Patent; Vergr.40 - 1200 refers to the magnifications in the range 40-1200x. The Protami is provided with a three objective turret which makes changing magnifications an easy and speedy process. Together with the draw tubes, this provides a broad choice of magnifications ranging between 40X and a theoretical 1450X, when used in the oil immersion mode. When the lower achromatic objective "T" (for "Tami") is selected, it provides the magnification sequence of 45-250 times. The "M" ("Metami") marked dry objective provides the magnifications of 340-760X, as indicated by the scale on the tube. The "P" ("Protami") objective is an oil-immersion of 1/12" with numerical aperture of 1.34, yielding the magnification range of 915-1450X. The microscope is equipped with an Abbe condenser with iris diaphragm, flip-up stage clip, substage slide-out canister containing a tube for immersion oil, and flat and concave mirrors on an adjustable arm. The stage can be flipped out of the optical path for easier access for the replacement of the objectives.