Pocket Fresnel lens for the small print
So, the way I heard the story . . . Several older and experienced hikers were hiking in the Columbia River Gorge. As light was fading, they needed to make a route choice at a trail junction. They pulled out their map . . . and couldn’t read it because no one had reading glasses! They didn’t know where to go, and decided to stay put for the night. (That was probably the best choice, and luckily they had the gear to do so in reasonable comfort.) The next morning, when there was enough light to read their map, they walked out unassisted.
For more “well seasoned” climbers, reading the small print on a map or phone screen can be tricky. But who wants to bring reading glasses on a hike or climb?
A lightweight, inexpensive, and functional solution is a pocket Fresnel (pronounced fruh-nel) magnifying lens.
image: https://www.amazon.com/Outus-Plastic-Reading-Magnifier-Firestarter/dp/B06W5FCS4Q/
These little puppies are simply thin, flexible, plastic magnifying glasses. About the size of a credit card, they are dirt cheap, magnify to about 3x power, and really help to read that 8 point font. (The image clarity is not as good as what you’d get with a lens actually made of glass, but it’s probably good enough to read your map and make the correct trail choice.)
If you want to show off your bushcraft skills, they can apparently be used in a pinch to even start a fire, provided you have steady hands, perfect tinder, and bright sunshine. (Disclaimer, I have never done this, your mileage may vary, and YouTube is your friend.)
You can get a multi-pack of pocket magnifier lenses online for something like $1 each. So, buy a bunch, keep them scattered around your gear bags, and give ‘em away to your friends. Search Google for “pocket Fresnel lens”.
Science geek note: the Fresnel lens was invented by a French physicist in the 1800s, and was originally used in lighthouses to concentrate the light beam. Several excellent examples can be seen at historic lighthouses, including several in Oregon. When seen full size in a lighthouse, they are quite amazing!
Fresnel lens in Cape Mendocino lighthouse, California. Image: Wikipedia
