By Deborah Price and Aaron Watson, IDA Colorado, 11/20/2022.
A lot of darkness in the winter means we depend more on good night vision when outside enjoying a twilight snowshoe tour or skiing down a cross-country trail. It may seem that a bright headlight is the best option for this, but that bright light may actually detract from the quality of your experience.
Once your eyes are exposed to a bright light, it takes at least half an hour for the rod cells in your eyes to re-adjust to darkness. A glaring light not only shuts down your pupils, but also draws your eyes towards that light and ignores everything else, isolating you from the surrounding environment.
Imagine walking through the woods at night with a flashlight on. Your eyes focus on the light ahead of you while all around you is pitch dark. If you turn the flashlight off, and take a few minutes for your eyes to start adjusting to the darkness, your natural night vision will kick in and you’ll start to see and be aware of everything around you. So go dark when you can for a wonderful nighttime experience.
When light is needed for outdoor winter nighttime activities, do what the astronomers do and try a red light because it has the least impact on your dark-adapted eyes and minimizes the impact of light pollution on the environment. Many headlamps come equipped with a red light setting for this purpose. If more light is needed, a green light is better for your eyes and for the environment than a blue or white light. A good practice is to use white light only in emergencies or other critical situations in order to have the least impact on your night vision, the environment, and those around you.
Another great way to experience the night is to plan accordingly and choose dates leading up to the full moon. The moon usually provides plenty of natural light for nighttime activities, and you’ll see so much more of the nightscape around you if you keep your artificial light to a minimum!
This winter, be safe and smart with artificial light at night. Let the natural light of the moon and stars be your beacon, have a backup light for safety, and enjoy the beauty of a cold, quiet, winter night!
For more information:
National Park Service: Dark Adaptation of the Human Eye and the Value of Red Flashlights