It was also run quickly under direct spray at least once per shower. During mechanized operations, everything, and everyone, gets coated with a fine layer of dust kicked up by an endless procession of tracked vehicles. To simulate this, we fitted the rubber objective cover over the lens, and put the scope into the mostly full bag of a vacuum cleaner. Then we vacuumed seven different carpeted rooms, swirling the PSO-1 in a dust storm each time. No ill effects noted.
Some people have casseroles in their freezers.
Some people have frozen vegetables. Some people have the turkey that was on sale last week. We have, or rather had, a PSO-1 in ours for two days. No ill effects noted. Wish List As good as the PSO-1 was, there were a few things we'd like to see to improve it.