When it’s 14°F / -10°C (at least that cold here), it is cold enough that when my shoe tread got wet down yonder, my shoes froze to the superchilled rocks as I walked on them, then made crunchy sounds as the tread/ice bond tore loose as I walked. Kinda cool*.
Cold conditions require special care so as to not fog the front of the lens (gah!). However, the humidity is also quite low under such conditions, so frozen breath on a front lense element generally evaporates quickly. Just don’t breathe on the rear element or sensor unless you want a LensBaby look.
As shown, frost can build up wherever one’s breath hits metal. In this cold, the Sony A7R II malfunctioned and would no longer auto switch between EVF and LCD. Later, it began to work again.
* When I had to “go’, it was fun to glaze a large rock in crystal-clear ice. That’s fairly cold to be able to freeze warm urine instantly. If you don’t think it’s cool, hike your ass out for a mile and then go drive to a bathroom somewhere, or pee on a tree—but you’ll miss the fun.
ProCamera for iPhone discussion below...