Tried cleaning fungus off a lens element with hydrogen peroxide and a UV light
I had this old 50mm f/1.4 that had some pretty stubborn fungus growth inside, nothing crazy but enough to show up in shots. I kept reading online that a mix of hydrogen peroxide vapor and UV light could kill and clean it off without taking the lens apart, so I figured why not give it a shot. Stuck the lens in a sealed bag with a little dish of 3% hydrogen peroxide, set it under a UV lamp for about 6 hours. Pulled it out and the fungus looked way less visible, maybe 70 percent gone after wiping what I could reach with a lens cloth. But I also noticed some haze on the inner elements that wasn't there before, almost like a residue left behind. So I ended up having to disassemble it anyway to clean that off with proper solution. Lesson learned: it might work for surface stuff, but for sealed internal elements, you're still better off cracking it open. Has anyone else tried this method and gotten better results without the haze?