Question: Who made the first single lens reflex instant picture camera? Answer: Polaroid. Right? Wrong. More than 60 years before Polaroid’s remarkable SX-70 instant SLR, the British Butcher company introduced the Dandycam.
 
It took tintypes, which formed a direct positive image on metal plates. These were circular, 2.5cm in diameter, and the image produced was for inserting into pendants and brooches. The plates were loaded into a compartment in the side of the camera and held in place by a strong spring. As a lever in the side of the camera was pulled out and pressed in again, the first tintype was pushed into position behind the lens which directed its image via an internal angled mirror up to a round viewfinder on the top of the body. This was covered in red glass because it was looking into the camera body and normal light would have fogged the sensitive plates within. Exposure was made by turning a knob on the side of the body that lifted the mirror so light could reach the plate. When the knob was released the mirror fell back into its original position to cut off light to the plate, completing the exposure and restoring the reflex image to the viewfinder.
 
The side lever was then pulled out, which released the plate behind the lens to fall into a tiny developing tank in the base of the body.
When the lever was pressed in again it pushed the next plate into position for the following exposure. The tank contained a one-shot developing and fixing solution which produced a fully developed positive image in about five minutes. So okay, five minutes wasn't exactly instant, but it did yield a fully developed image a lot faster than exposing a conventional plate that needed to be developed and a print made from it in a darkroom – and it is was a sort of SLR that even had a kind of instant return mirror.