I was having major issues getting the Circular Polarising Filter off the front of my 17-55mm lens. Its a 77mm diameter lens and quite wide, so I was having trouble getting a good grip amd was beginning to think I had cross-threaded it.
Went into local expert camera shop to ask about a few things, and ask for help with getting the filter off. Imagine my utter embarrassment when he calmly unscrewed it easy as pie.
The trick is NOT to squeeze to tightly – it deforms the outside frame and therefore won’t unscrew.
Put as many fingers as you can get evenly around the outside, apply light even pressure on all points and WALLAH! should just come right off 🙂
Of course if you *have* cross threaded it, then thats another story entirely!