[ralph1]

I've noticed in the last few nights that while using binoculars, the left eyepiece constantly fogs up - as in within 20 seconds of putting it to my eyes. The right eyepiece has no problem and neither do the objective lenses. To get rid of the fog, I need to stop using the binoculars for the next 20 seconds, and it is an annoying interruption to my observing.
I usually use them with the eyecups extended, lying on the ground, resting the eyecups against my eyes.
Why is it only with the left eye?
Any help would be appreciated.
Ralph