Optolyth Alpin Classic 10×40

Specifications:

Objective diameter:  40 mm
Magnification:  10 x
Exit pupil: 4.0 mm
IPD: 52  –  71 mm
Usable eye relief (measured from rim of folded eyecup): 10.5 mm
RFOV:  5.8  degrees = 102 m
AFOV (measured, rounded):  59 degrees
Minimum focus distance (measured): 3.85 m
Focus type: CF (direction of rotation from close to infinity: < anticlockwise)
Degrees of rotation of focus wheel from 3.85 m to infinity (measured): 470 degrees
Range of diopter adjustment (estimate): +/- 5 dpt*
Excess travel of focus wheel beyond infinity position (estimate): 8 dpt*
Prism system:  Porro I
Waterproof: splashproof
Weight (measured, with eyepiece cover and strap): 591 g
Made in: Germany
*range of diopter adjustment not affected by position of focus wheel

Remarks:

The Alpin series was Optolyth’s venture into the Porro design; currently, the series is not produced anymore. The Alpin 10×40 may have been one of the lightest 10×40 binoculars ever; its optics were okay (not up to the current standard of similarly priced binoculars), but mechanical quality was only average (bridge rocking); its heavy rubber armour makes it look very solid, probably more so than it actually is.

see also remarks in separate posts
“Optolyth Royal 8×56”, https://binocular.ch/optolyth-royal-8×56/
“Optolyth Royal 9×63”, https://binocular.ch/optolyth-royal-9×63-2/

Ratings: