Hartmann Compact 7×42

Specifications:

Objective diameter:  42 mm
Magnification:  7 x
Exit pupil: 6 mm (spec), 5.6 mm (measured)
Eye relief: 17mm (acc. to spec)
Usable eye relief (measured from rim of eyecup): 6 mm
IPD:  52 – 74 mm
RFOV (acc. to spec):  8.6  degrees = 150 m
RFOV (measured): 8.2 degrees = 143m
AFOV (measured, rounded): 53 degrees
Minimum focus distance (measured): 3.3 m
Focus type: CF (direction of rotation from close to infinity: < anticlockwise)
Degrees of rotation of focus wheel from 3.3 m to infinity (measured): 685 degrees
Range of diopter adjustment (acc. to spec.): +/- 3 dpt*
Excess travel of focus wheel beyond infinity position (estimate): 2.5 dpt*
Prism system:  Porro I
Waterproof: splashproof (?)
Weight (measured, with eyepiece cover and strap): 818 g
Made in: Germany
*range of diopter adjustment not affected by position of focus wheel

Remarks:

Hartmann Optik Wetzlar manufactured this instrument in the early 1970s. It was part of their “Compact” series of binoculars introduced in 1966 (6×30, 7×35, 7×42, 8×30, 8×40, 10×40), with a wide field of view of 150m (the present sample shows actually less than that), good central and amazingly good edge sharpness, and a slightly yellowish image (later production models with better coatings did improve on this). Despite its 17mm of eye relief, this model was barely usable by spectacle wearers since the eyecups made of bakelit could not be folded down. Hartmann Optik, which had started to produce optics in 1921, closed down in 1992.

Ratings: