Tried cleaning a 70s lens haze with a homemade mix and it went sideways

Got this old Pentax 50mm in last week with that classic yellowed haze from age. Instead of my usual pro cleaner, I thought I'd try a trick I read about online, a mix of white vinegar and distilled water. Figured it was gentle, right? Well, after letting it sit for a few minutes, the haze didn't budge, but the vinegar seemed to react with something in the cement. It left these faint, cloudy rings between the elements that I couldn't polish out no matter what I tried. The lens is basically a paperweight now. I guess the lesson is that old glues and coatings can be a real wild card, and sometimes the old school methods are too simple for a complex problem. Ever had a 'gentle' fix totally backfire on vintage glass?

2 comments

2 Comments

the_tara20h ago

Ever tried to be gentle and just make it worse? I once used a "safe" lens wipe on an old coating. It took the haze off, sure. It took the whole coating off with it. Left a weird rainbow smear. Felt like I polished a hole right into the glass. My heart just sank. That lens lives in a drawer now, a monument to good intentions.

lily9718h ago

Vinegar is actually pretty strong stuff, it's an acid. Tbh, that's why it can eat at old lens cement. The haze is often in the glue itself, not just on the surface, so any liquid that gets in there can cause problems. A lot of those old recipes don't account for how the glass and glue have aged. It's a real shame it etched the glass, that's the worst outcome.