Mamiya RB67 with 127mm F/3.8 LensThe RB67 Professional was introduced in 1970 with a similar look to conventional medium format SLR cameras like the Hasselblad, but was larger due to the 67 cm frame format, closer to the typical 810 inch aspect ratio of portraits. However, the RB67 differed visually from other 6x7 cameras of the time, which resembled very large 35 mm cameras.[3]: 168 There are three successive models: the RB67 Professional (first model released in 1970), RB67 Pro S