Pro tip: that yellow haze on old lens cement isn't UV damage, it's balsam separation starting
Compared a 1968 Nikkor 50mm before and after a 2 week soak in xylene and the difference was night and day, the haze was balsam going soft not coating breakdown. Anyone else seeing this get misdiagnosed as fungus on old Pentax glass?
Wait, 2 weeks in xylene?? I've always been told xylene soaks will eat through the coating or wreck the glass if you leave it too long, and you just let a lens sit in it for 14 days with no damage? That completely changes how I look at these hazy old lenses, I've passed on so many cheap Nikkors and Takumars because I assumed the haze was coating rot. So did the balsam fully dissolve off or did you have to re-cement the element after?