the good doctor on: "One Winter Morning"
Blog #42 “One Winter Morning”
This is the first line in Ezra Jack Keats “The Snowy Day”,
“One winter morning Peter woke up and looked out the window. Snow had fallen during the night. It covered everything as far as he could see.”
Oh, to see the fluffy white stuff from a child’s perspective again. When you become an adult, it is your adversary — you have to drive in it and shovel it, not make castles or angels.
You also have to deal with glare. Snow and ice can produce the most awful glare (and UV light). This time of year also has the low-lying sun in the morning and evening skies. That combined with the ice produces some wicked glare. Solution? You could commute west in the morning and east in the evening, that would definitely help. You could also invest in some sun protection.
High tech sun filters cut full UV, select out more trying wavelengths of light, and cut down on the reflected light off of the snow. Light travels in a wave pattern, but a wave in all directions, about 50% going up and down and the other 50% going side to side. When light reflects off a non-metallic surface, for example ice, it changes polarization, with the vast majority of the light now travelling side to side, or transverse. It is even worse when more light is reflected, such as when the sun is lower in the sky.
The invention of the polaroid filter was a big help for dealing with this glare-producing light. These lenses select out the transverse waves, and filter them, allowing the up and down waves to pass through. The result is enough light to see the object, with the most bothersome light removed.
Now we have polarized sunglasses for serious anglers and drivers and people who live in snowy places. It works so well, all windshields for commercial airplanes are polarized (you can imagine the glare that occurs around a plane). At Burlington Eyecare, we use a combination of prescription or non-prescription sunglasses with either Nikon lenses or more advanced Maui Jim filters…
An answer for Jack Frost’s handiwork.
Til next week
the good doctor, Dr Mark Germain, Burlington Eyecare.
