One of the gear choices for thru hiking that I've still not found a fully satisfactory option for is eyewear. Currently, I wear my contact lenses with wrap around, polarized sunglasses. The sunglasses are worn when it's bright and I can quickly push them to the top of my head or place them up on my cap when I don't need them. It's a quick transition and this option provides 20/20 vision while protecting my eyes from bright sunlight. However, I have several issues with taking my contact lenses on longer hikes. I need to carry extra gear; namely, a case for the lenses, protein cleaner, storage solution, and re-wetting drops. Granted, these take up very little space in my pack and, collectively, add just an ounce or two to the pack weight. Nevertheless, they mean I have to track several more items when packing my gear.
Another issue is eye health. It can be dry and dusty on the trail which compounds the dryness that can come from wearing contact lenses. If my eyes become too dry then there is an increased risk of infection or other vision issues. The final primary concern is that these lenses are tiny and difficult to see. I often set up camp as darkness is falling and removing those small lenses requires a great deal of care. If I drop one of them I'll probably never find it again. I never have lost a lens, but it's a constant worry when I take them out at night and when I put them back in the morning.
I would prefer to wear my eyeglasses when hiking for these reasons. The problem is that I haven't yet found a good solution for dealing with bright sunlight. The clip-on and flip-up sunglass lenses I've tried let in far too much light from the top, sides, and bottoms. I have prescription sunglasses, but then I have to stop and change glasses (which requires putting them back in their case and safely stowing them) every time I transition from sunlight to moderate light, e.g., I walk from an open field into a forest. I'm not interested in laser surgery and ruled out that option many years ago.
My current plan is to revisit the possibility of flip-up sunglasses. They will attach to the bridge of my eyeglasses and I can simply flip them up (while remaining attached to my eyeglasses) when I don't need them. I will focus on lowering my hat so that the brim does a better job of blocking sunlight from entering from above. I don't know if this will work and there is a chance that my eyeglasses will tend to slip down my nose due to the fractionally increased weight. In the end, though, they only cost $10 and I think it's a worth a try.
Having said all that, I did wear my contact lenses on my last camp. Here's a video that shows my process for proper cleaning and storage when in the field. It's essentially the same as doing it at home but I need to be much, much more careful that I don't drop a lens.
