A banquet camera is a type of large format camera used in the early 20th century for photographing large groups of people in formal occasions.
Specifications
The film format of banquet cameras were of narrow aspect ratio, with formats of 7x17 in. and 12x20 in. being common. Their use died out as enlarging smaller formats became more popular [1] wide angle lens use increased, and the snapshot aesthetic became acceptable to record even highly formal events.
References
Banquet camera Wikipedia(Text) CC BY-SA