Mountains and water offer similar challenges for good eyewearlots of glare, the need for excellent contrast, and a requirement for good protection from UV rays. On snow, its also important that glasses offer protection on the sides, although there are several different ways they can accomplish this. It would help if they dont break the bank, but a good pair of sunglasses is a worthwhile investment in safe vision.
You mentioned three that youve looked at: the Zeal Optics Maestro ($130; www.zealoptics.com), the Julbo Nomad X4 ($104; www.julbousa.com), and the Native Nano 2 ($115; www.nativeyewear.com). The Zeal glassesone of Outside magazines Gear of the Year" award-winnershave a generous wrap design for side protection. They come with a polarized ZB13 (Zeals label) lens, and have an option for a polarized brown lens for slightly greater light reduction, although its a very slight change, so Im not sure its worth the bother. Overall these would work great on snow or water.
Julbos Nomads are more of a traditional glacier glass. They have snap-out side protectors that offer a little more coverage than the Zeal glasses, and their brown progressive lenses offer light reduction of 87 to 95 percenta little darker than the Zeals. If you intend to be on snow a lot, then these might be the best choice. In my opinion, however, theyre not quite as fashionable as the Zeals.
The Native Nano 2s, while an excellent pair of glasses, might not be the best choice here. Theyre a little bit more of an all-purpose glass, with decent side coverage but not the extensive coverage of the Zeals or the Julbos. They do, however, come with four interchangeable lenses from dark to clear, so that might be a consideration.
I think you have a good set from which to choose. If your time is split 50/50 between water and snow, then probably go with the Zeals. If its split 30/70, with the 70 on snow, particularly mountaineering at higher altitudes, then go with the Julbos.
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