Originally Posted by TheFlyingCamera
The interesting thing is that, at least historically, you could occasionally get away with producing an unflattering portrait on commission.
Take for example using a 450 mm lens on a 20x24 camera and making President Obama look like he took a selfie.
"There are a great many things I am in doubt about at the moment, and I should consider myself favoured if you would kindly enlighten me. Signed, Doubtful, off to Canada." (BJP 1914).