Hello Jerry,

I've allways used dew caps on my scopes. And I was thinking of how to adapt this on the binoculars and the mount. Until now I have not taken any actions to prevent dew.
According to the manufacturer, the mirror is the last optical surface to dew up. This sounds very strange. But I did a test. After a night of observing, I brought the unit back indoors without covering the optics. The binoculars and the mount started dewing up immediately, but not the mirror. Trico Machine had many questions from their customers, as why the mirror does not dew up. Actually Trico does not know why, but the mirror seems pretty dew resistant. Of course, when circumstances are very humid, all surfaces will dew up. So if you need to take measures against dew, it will be on the binoculars first.