Pro tip: I stopped using compressed air on mirrors after a Nikon F3 taught me a $12 lesson
For about six years I blasted every dirty mirror and sensor with a can of compressed air because it felt fast and easy. Then a client brought in his late dad's Nikon F3 from a garage in Duluth, and one hard blast sent propellant spots across the finder glass that took me 40 minutes and a fresh swab to lift off. Now I use a rocket blower for loose dust, a static brush for the stubborn bits, and a wet swab only when the coating actually needs it. The whole change came down to one afternoon where I made more work for myself than the camera had. Anyone else got a cheaper first step they reach for before the wet clean?