But legally you are supposed to follow the instructions of the crew.
er. Not quite.
You are required to obey the
legal commands of the Captain.
Is that command legal? I doubt it.
It is highly unlikely to be "illegal" to use a camera in flight, and if it was it is a matter for the civil authorities in the country in question and nothing to do with the airline unless thay choose to report you. It is even less likely that the cabin crew know local laws in that sort of detail, isn't it?
It may be against the company's Ts and Cs of carriage (doubt that very much) and I'd want to see that in writing before I put my camera away. The only legal aspect is
failure to obey etc, and that is nothing to do with a cameras.
It's unlikeky that you'd be held to be in breach of the "captains instructions" if you hadn't had a specific warning to that effect first, particularly for something as trivial as that.
Finally, we are told that the Captain has no legal command over pax until the doors are closed. It may not be as simple as that in reality (declining to carry you for various reasons, but use of a camera cannot be one of those.) but that is the legal position.
Let's see that instruction in writing first anyway, or is it just crew throwing their weight around? I know where my money is.