pduxon said:
Leif and anyone else
why don't the likes of Zeiss, Swaro, Leica make porro prism bins?
Pete,
I own a pair of the Swarovski porro-prism 10x40 W glasses, which I bought on eBay secondhand but in virtually new condition for a great price. I really don't like 10x binoculars much for birding, but thought I would try them at regional Hawkwatch sites. I used a pair of 8x30 Swarovski porros briefly once and was impressed, so thought I would give the 10x40s a try.
The build quality and finish is high. Swarovski claims their porros are the only nitrogen purged and truly fogproof porros on the market. They are very sharp, but their contrast is less than the Nikon SE, the new Ultravid, and some other great binoculars, so the apparent resolution is diminished slightly. Color fidelity is exceptional. Chromatic aberration is sometimes obvious and appears as a dull red fringe around contrasty subjects. Despite the dated design (the original Swarovski porro in this style, a 7x40, was released in the late 1940s) ergonomics are good, at least for my relatively small hands. FOV is the same as many 10x binos on the market--330 feet @ 1,000 yds.
One helpful feature is that the objective lenses are deeply recessed--about a half inch--which protects them effectively. Eye relief is shallow, making them undesirable for use with eyeglasses. It also causes eyelashes to touch the oculars, which makes cleaning a necessity more often. The folding eyecups are easily removed/replaced.
The seals that make these waterproof are between the ocular barrels and the barrels behind the prism housing. When a glass is new, these are very tight, making focusing difficult. Mine has loosened quite a bit. However the focusing wheel is small, metal, and finely grooved, and focusing in cold weather, either with cold fingers or a gloved hand, is not as easy as on other premium binoculars.
Altogether these are very good and underrated/overlooked.
Leif mentioned some drawbacks of Nikon SE. I personally consider the ergonomics exceptional. But aside from lack of waterproofing and the dated rubber eyecups, Nikon might at least have made the eyecups removeable for cleaning and replacement, like Swarovski and Zeiss have done.