Well, today's PAD came to me. There he was sitting on my windowsill waiting to be fed.
First I had a go through the window, expecting him to fly off. He didn't so I put the polariser on to cut out some reflections (doesn't cut through the grime though!). He still didn't fly off, so I tried opening the window - and he STILL didn't go!
Didn't get a chance to try a different lens though. Hope 'he' is a 'he' and not a 'she'!