Introduction
There are times when one wants to carry a binocular, but for various reasons it simply is not practical to carry a large instrument. Even an 8x30 roof prism binocular is fairly large and heavy and would not fit in a shirt pocket. Hence the popularity of a small 8x20 roof prism binocular that in good light provides most of the performance of a full sized instrument, and yet folds down into a shirt pocket sized package.
Design and Build
The Zeiss 8x20 Classic is a traditional roof prism binocular, consisting of two parallel tubes, connected via hinges to a central bridge. The housing is made from a hard dark grey plastic, whilst the lens cells are made from metal.
The focus wheel and dioptre wheel are mounted at the rear of the bridge, the focus wheel on the left, and the dioptre wheel on the right. A rather nice feature of the design is that left-handed users who prefer to have the focus wheel on the right can simply invert the instrument. The coarsely knurled focus wheel rotates very smoothly, and, for me anyway, is perfectly positioned for the little finger on my right hand. The dioptre wheel is smooth, and the rotation is fairly stiff to prevent it from accidentally moving from the desired setting.
The eye tubes are made from a fairly stiff rubber and fold back for eyeglass users: I found folding them back to be a very fiddly process.
The binocular folds into a remarkably tiny package for storage in a shirt pocket, a coat pocket, or the corner of a briefcase.
The binocular weighs under 200g and is thus extremely light.
Overall build quality and styling is very good. I have taken one on numerous four mile runs around the local nature reserve, and thus far it has survived without any problems.
As far as I know the binocular is not waterproof. In any case, it is so small that it is easily sheltered from the rain.
Optics
In good light the binocular provides a surprisingly good image with very good contrast and excellent sharpness over a large part of the field. Tested on a resolution chart the binocular compares well with larger instruments. The field edges are a bit soft, due in part to field curvature, but in practice the softness is insignificant. There is some distortion, which is evident when panning, and this is perhaps the only weakness.
In overcast conditions the small objective are all too apparant, though resolution is excellent.
The binocular has a tendency to flare when viewing towards bright light, which can be reduced somewhat by using one hand to shade the objectives.
I noticed no obvious colour cast.
The field of view, 110m at 1km, is less than on most high end full sized binoculars, but is quite acceptable. As with most compact binoculars, eye relief is not large and some people will have trouble seeing the whole field while wearing eyeglasses. Ideally it should be used without eyeglasses.
The close focus is approximately 3m.
Accessories
The binocular is supplied with a rather nice case made from leather, although to my disappointment the seams appear to be made from plastic strip.
One potential problem I noticed is that if the binocular is placed in the case with the eye tubes folded down there is a real danger that the eyepiece lenses could come into contact with the zip and suffer damage. The solution is to store the binocular with the eye tubes extended.
The binocular comes with a cord neck strap. It is not supplied with a rain guard or lens caps.
Cheaper Alternatives
For significantly less money excellent optical quality can be obtained from an inverted porro-prism binocular, although none are anything like as compact as the Zeiss 8x20.
Comparisons
I compared a Zeiss 8x20 Classic with a more expensive Swarovski 8x20 B (I bought the Swarovski and inherited the Zeiss). Optically they are very similar. Both have excellent contrast and sharpness over most of the field. The Swarovski has a slight edge as it does not have as much edge distortion or field curvature as the Zeiss, though the differences are small. Mechanically they are rather similar, though the Swarovski has screw-in screw-out eye tubes that are more convenient. Neither is comfortable when used with eyeglasses. The position of the focus wheel is highly subjective, but I prefer the Zeisss: I initially found the Swarovski focus wheel hard to use, though with time I have come to rather like it. The Zeiss focus is neither especially fine nor coarse, whilst the Swarovski focus is finely geared, making focussing finer but slower. In the UK the Swarovski costs about 280 compared with about 215 for the Zeiss.
Other alternatives include the Nikon 8x20 HGL, the Zeiss 8x20 Victory and the Leica 8x20 BCA. I have only briefly tested these instruments, but it was obvious that all have first class optics, with similar performance, and excellent build quality. Perhaps the most obvious differences are the position of the focus wheel, and the size of the folded binocular: the Leica and the Zeiss Classic are both noticeably smaller than the Nikon and the Zeiss Victory. In terms of price the Zeiss 8x20 Classic stands out, as it is by far the cheapest. An alternative is the Opticron 8x21 DBA Oasis, which has a noticeably wider field of view, and much larger eye relief than any of its competitors. Although the image has significant distortion, the overall package is very impressive, and well worth a look.
Conclusion
Overall the Zeiss 8x20 Classic is an excellent little binocular. It is not really suitable for general birding due to the small objective. However, it is well made, stylish, and has excellent optics although the fiddly rubber eye tubes will not suit some users. At about 215 in the UK it is excellent value compared with competing products. If you need a compact binocular with high quality optics, I can recommend the Zeiss 8x20 Classic.
A warning
Many people like to keep a compact binocular on a windowsill, or side table, ready to view birds in the garden. However, a binocular such as the Zeiss 8x20 Classic is readily pocketed by dishonest visitors, as my mother found to her cost. It wise to keep it hidden from the eyes of potential thieves.
