Essential nest box fix

Last night the box was empty, so I did the swap over, and it all went fine. It was a bit tricky with this box, as it’s in a tree fairly high up on the edge of my property. I took the whole box down and put it on the bench to have a look. The IR sensor seemed clean enough, and the only thing I noticed was the lens lock ring was loose, and the lens fairly loose too. So possibly it moved out of focus when I relocated it? I don’t remember adjusting the lens though, and it seemed very clear during the day?
Everything seems fine now after the swap, and we had a visitor throughout today.

I’ll speak to the supplier tomorrow to work out my options. 

Thanks again
Steve