Funnily enough, I think this depends on country. I’m in Australia and I’ve heard lecturers ask the class not to call them Professor since that is a title within the University (I’m guessing something similar to Captain in an Army). I think most couldn’t care less, but I’ve had 1 or 2 ask in the first class not to use that title. So you can’t win.
Guess this is why I like college. I just call everybody Professor and not risking strange looks or offending anybody.
Funnily enough, I think this depends on country. I’m in Australia and I’ve heard lecturers ask the class not to call them Professor since that is a title within the University (I’m guessing something similar to Captain in an Army). I think most couldn’t care less, but I’ve had 1 or 2 ask in the first class not to use that title. So you can’t win.