Simple aids for watching the full moon Take a look at the full moon and you might be surprised how many details you can see without a telescope. If you look closely, a good dozen of the dark seas and a handful of craters are visible to the unaided eye. There are easy ways to take the full moon experience one step further without having to revert to optical equipment such as binoculars or telescopes. You can start with your favourite beach sunglasses. Regular shades or polarizing glasses help soften the glare and thus enhance contrast slightly. You will see the mare stand out more prominently and in even higher detail. A neutral photo filter is another simple piece of equipment for contrast improvement. It’s most likely that there is one such filter in your photo case. They are inexpensive and easily available. Just hold it in front of one eye. You can even keep the other eye open. Much better even are yellow color filters. We observed the best results with a Wratten filter #12, a deep yellow. Wratten numbers are a labelling system for optical filters frequently used in photography and astronomical observations. The contrast improvement with this filter is quite stunning, like observing the moon from high up in the mountains. The image below shows a simulation of the contrast improvement that can be achieved with a Wratten #12 color filter held in front of your eye.
full moon contrast improvement with yellow filter