A retired tech in Ohio told me to stop using alcohol swabs on sensor glass, and I owe him a beer
I was cleaning a Canon 5D Mark III sensor for a client in Columbus and kept getting these faint streaks no matter how many times I wet swabbed it. A retired repair tech named Dale who hangs around the shop told me to ditch the pre moistened alcohol swabs and try a dry sensor brush first, then a single wet pass with Eclipse fluid only if needed. I figured he was stuck in the 90s and ignored him for 3 cameras, but the streaks kept coming back and one client even brought their body back twice. Finally I tried his method on a beat up 6D and the difference was night and day, zero streaks and way less fluid. Now I'm torn because half the forums say dry brushing just pushes dust around and can scratch the filter, while Dale swears it saved him hundreds of sensor replacements over 20 years. So who's got the real story here, are you team dry brush first or team wet swab only? And has anyone else had an old timer hand them a trick that sounded wrong but actually worked?