Alpen Teton Binoculars

The Tetons are a new binocular line released by Alpen in mid-2007. This is a relatively high-end product for Alpen, falling in below only the Rainiers (see review) in price at $585 for the 8x42 model and $600 for the 10x42 model, putting the Tetons right in the middle of the mid-price range bracket among optics. Like the Rainiers, the Tetons are a roof prism design, and feature the same SHR™ metallic coatings and PXA™ phase-coating as their more expensive cousins. The primary difference between them is that the Tetons don’t have the same high-tech UBX™ multi-coating as the Rainiers. Beyond that less-than-obvious difference, not too much appears to separate the Tetons from the Rainiers, which is great news for those who want to buy binoculars. But we’re getting ahead of ourselves. Why this is great news is what the rest of this review is about.

At first glance, the Tetons look like a slimmer, more rakish Rainier. The barrels are a bit more slender, the hinge region isn’t quite so broad, the slightly flared upper portions with recessed lugs for the strap, and the focus knob isn’t quite so broad but much else looks the same. The dark green rubber armor is typical of all Alpen’s products, the focus knob has the same aluminum accents and the eyecups have the same sort of blocky design as on the Rainiers, (as well as the Apex and the PRO Waterproof). Dimensions on the Tetons are as follows: 6 inches high by 4.9 inches wide, and weighing 27.0 oz. for the 8x and 27.6 oz. for the 10x. In this case, the slightly smaller dimensions and substitution of a composite frame for the magnesium one of the Rainiers probably accounts for the lighter weight of the Tetons. Like all Alpen roof prism models, the Tetons are made with BaK4 glass, and are sealed and nitrogen-purged to be waterproof, dust proof and internally fog proof. The Tetons are nicely balanced, and have a great feel in the hands.

We were very pleased with the optical performance of the Tetons. It’s true: the Rainiers outperformed them for brightness of image, particularly in low light conditions, but that is the expected result. When we tested the Tetons against other binoculars in the $500-$700 range, they outperformed most of the competition. The brightness was excellent, the image tack sharp, and the color fidelity terrific. You would have to spend at least $200 more to get significantly better optical performance. The flat field performance was better than average. There is a tiny bit of distortion at the very edge of the visual field with a bit of chromatic aberration there as well, but this zone wasn’t particularly large as these things go. The tendency towards pin-cushioning was relatively minor. Overall, the Tetons have a very good flat-field performance, especially in a $600 optic. The field of view (FOV) at 1000 yards is 383 feet on the 8x model and 341 feet on the 10x. Thus, the Tetons have about 5-6% better FOV than average in the 8x and 10x classes for 42-mm optics, a fairly significant difference. Though listed as having an 8.2-foot minimum close focus in the Alpen literature, we measured the minimum close focus at 5.5 feet for both Teton models with no tendency towards field collapse. Again, this is better than average performance for 42-mm binoculars of any magnification or price. Commensurate with this excellent minimum close focus performance, the Tetons don’t have a particularly great depth of field, but this is an expected trade-off. The precision of the focus mechanism does a little to compensate for this in practice. The Tetons go from minimum close focus to infinity in just 1.25 turns of the focus knob, which is a little bit higher “pitch” to the focus mechanism than in many binoculars – our data show the average being closer to 1.5 turns. There are advantages and disadvantages to this. The higher pitch means that things snap into focus with a little less effort, or blow right past it, the difference being how used to the mechanism you are. Balanced against that, the mechanism has a nice degree of resistance against the turning of the knob, so you tend to blow past things less. These things do come down to a matter of taste of course, but the Tetons suited our taste in this regard.

Both models of the Tetons have 17 mm of eye relief, more or less average for either class In point of detail, it’s a little more than average on the 10x, a little less than average on the 8x. We measured the interpupilary distance range at 58-74 mm on both versions of the Tetons, a little smaller range than average for roof prism binoculars. This means that if you have particularly widely- or narrowly-set eyes, you might want to check these for fit. Generally speaking though, this shouldn’t be an issue for most people. The Tetons did really well on the two user-adjustable characteristics: eyecup positioning and diopter adjustment. The eyecups adjust with the ubiquitous helical-twist mechanism, counter-clockwise to extend them and clockwise to collapse them. The eyecups adjust through 5 discreet positions: fully-in, fully-out and three positions between. The intermediate positions are stabilized by what we would characterize as hard detents. In fact, on one of the two models we tested, the mechanism was a bit crotchety – the positions were so hard it was sometimes difficult to move them. The other one worked more smoothly, but the intermediate positions were still notably firm. Alpen gets high marks for this. Not to launch into a major polemic here, but too many binocular manufacturers make a claim for intermediate positions on their eyecups, and in fact, said positions are so unstable that inadvertent collapse of the eyecups is a major annoyance. Not so, the Tetons! The diopter adjustment on the Tetons is a twisting aluminum ring on the right ocular tube, featuring a pebbled sub-ring of rubber armor to assist the grip. A raised ridge in the armoring of the ocular tube lines up with a red hash mark on the ring to denote the position for equal eyes. The red hash mark is flanked by seven black hash marks on either side. Each hash mark, and halfway between each hash mark is marked by a shallow detent. Thus, while the mechanism does not lock, positions for unequal eyes are relatively easily remembered and recovered. If the ring moves, and you’re 4.5 clicks left, you’re back in an instant. So even though it is not a locking mechanism, it’s still a remarkably easy mechanism to use.

The rain guard, objective lens caps, strap and case supplied with the Tetons are virtually identical to the corresponding items that come with the Rainier, so we’ll confine our coments to telling what we like or don’t like. The rain guard is the usual soft rubber type, fitting snugly but easily over the eyecups, and not falling off when the binocular is inverted and shaken. This is good. The tethered objective lens caps have really deep flanges that fit inside the rubber armoring of the barrels easily but securely. One fringe benefit to the slimmer design of the barrels on the Tetons is that the tethers fit more easily between them, meaning that the lens caps aren’t always getting hung up between the barrels (and as a function of Murphy’s law, invariably obscuring the view!), which is a little annoying on the Rainiers. The strap is a nicely padded affair that should be fairly comfortable even on long days, particularly given the lighter weight of the Tetons. Unfortunately, it really isn’t long enough and some users may find this an annoyance. On the Plus side, it has the same refinement as on the Rainier strap: it actually comes apart in two places. There are short strips that thread through the recessed mounting brackets on the barrels, and have little double pressure clips that link to the main part of the strap. This means the strap can be easily detached from the binocular when putting it away, and then just as easily re-attached the next time it is used. This is a really nice little touch. The case is the same, roomy faux-leather pouch with a Velcro closing flap. It comes with its own strap, which mounts on metal rings on the side of the case. It has an outer pouch for thins like lens cloths or other small items. It is easily large enough to accommodate the binocular with its eyecups fully extended, and the folded strap as well. The case also has some padding to cushion the binocular in the event of an accident. This is an excellent case!

In the final assessment, we really like the new Tetons. You are getting excellent optical performance at a great price, and a lot of the small little features that improve the look, feel and ease of use. This binocular has a lot of features that some high-end optics really should be providing but don’t. We think Alpen has a real winner here
.

Alpen Teton Binoculars - current price and availability