As a guide, what does Quan Huafu mean in the middle picture of photography?

Medium frame refers to the imaging size between a small frame of 36×24mm and a large frame of 4×5 inches. At present, the medium format film camera uses 120/220 film with a width of 6cm, and the imaging dimensions are 6X4.5cm, 6X6cm, 6X7cm and 6X9cm.

Quan Huafu's goal is the size of the traditional 35mm film. In the past, the size of digital SLR CCD was smaller than that of 35mm film, and the size of Quan Huafu digital SLR CCD (or CMOS photosensitive imaging element) was the same as that of 35mm film. The larger the CCD size, the higher the imaging quality.