Tomorrow I do a walk-through of a Philadelphia in advance of a team meet-up and I wanted to take a bunch of pictures.  The week had been long so I kicked back and decided to clean all my lens filters with more care than I normally use so instead of using just a piece of low lint paper and isopropyl alcohol, I used Windex and cotton swabs.  I spent a good 10 minutes on each side and after two hours was quite happy with the result until one of the filters dried and was covered in streaks, streaks that didn’t seem to wipe out.  I went to the manufacturer’s web page and found this:

“When cleaning this polarized multi-coat filter DO NOT use commercial glass cleaning agents as this may result in the removal of the polarizing coating.  Only use water or rubbing [isopropyl] applied with a lint free cloth.”

So, while I engaged in destroying a lens filter, at least I engaged in the artisan, old-world, hand-crafted destroying of a lens filter.