Cold wont effect the speedglas lenses, actually its just the oppesite heat will effect them. Theres been a few times when i was running the Tig at 300+amps at work and had a ton of heat coming off the part and mine shut itself down on me. Had to let it sit for about 2 mins to get it to work properly again but i dont think thats what happened to you Pro because you were just tacking so there shouldnt have been any overheating problem.

You guys arent along with the bad eyes, even at 33 my eyes arent anywhere near what they were even 5 yrs ago

BG