I have been researching an idea that I have been hearing for a while:
It’s not a good idea to use a shotgun microphone indoor.
I want to check this question out and, eventually, make some tests. Here we go!
Thanks for the link!
Even the best shotgun mics are essentially omnidirectional at low frequencies. This happens to line up with where the greatest indoor noise intrusion typically falls - in the low frequencies. Fortunately for dialog we don't need much below 100 Hz but for recording anything else they will accentuate the lows - as the mic is picking up low sounds from all directions but highs from only one (and those nasty side lobes).