One point that Ludwig made, PP, was expressed in the words, "Probably not" and another as, "I don't know, QM." I certainly took both of these points, so just which points are you claiming, in a disparaging way, you aren't sure of my having 'taken'?
I should have thought it perfectly plain from the first contribution I made to this thread that I was, at best, tentative about the legal situation here. I did so by writing "as I understand it" and then putting the word crime in inverted commas. This is a standard literary technique for telling the reader that the writer is far from sure that the word thus enclosed is the correct word. Perhaps you're unfamiliar with it?
You keep suggesting that anyone is free to do what they like as regards recording police activity. I then presented a scenario of a cameraman filming police during what they would wish to be a surreptitious approach and possibly disturbing officers or alerting the suspect. Would that not be covered by the offence of "obstructing a police officer..."? If so, it would surely mean that it ISN'T just acceptable to record police activity on a whim, wouldn't it?