Docter 8x22B Aspherical

Docter (now under Analytik Jena AG) took over the binocular line from Zeiss Jena in 1991.  Docter incorporated aspherical lens elements into some of their binoculars.  Using an aspherical surface helps to improve the optical correction and eye relief without adding additional elements.  In addition to the 8x22B, there is also a 10x25B, both with standard and aspherical models.  I believe that these models are still available, though they are very difficult to find in the United States.

Docter 8x22B Aspherical

Mfr: Docter, Eisfeld, Germany

Date: circa 1990's

AFOV: ~55 degrees

TFOV: 120m at 1000m (~6.86 degrees)

Eye Relief: ~17mm

Prisms: roof

Serial Number: 40103116

This is a compact roof prism model with a rubber coated body and rubber eyecups.  Turning the small focus wheel moves the objectives.  On my sample the focus mechanism is a bit rough.  There is just the start of a light leak in the optical image.  Otherwise, the image is very well corrected, with low distortion, and a flat, sharp field all the way to the edge.  Docter literature indicates that the roof prisms have phase corrected coatings and silver reflective surfaces.  The optical quality does appear to be vastly superior to that found on the usual inexpensive roof prism models.  With the rubber eyecups folded down, I found this model to be usable with glasses, a rarity with compact binoculars.