What's the difference between camera SLR and double reflex?

SLR is the abbreviation of single-lens reflex camera, which uses the same optical mechanism for taking pictures and framing, so it can achieve the effect of "what you see is what you get".

Double-reflex camera is the abbreviation of double-lens reflex camera, which uses two independent optical mechanisms to take pictures and take pictures, and is commonly used in 120 frame system. Seagull 4 series machines are well-known in China and have stopped mass production for a long time.

The biggest difference between double-reflex and SLR is that double-reflex framing has a position difference (that is, the height difference between the two sets of lenses), which will cause inconvenience in framing when shooting close-up objects.

Structurally speaking, the double inverse ratio SLR is simple, so when it was popular in the market, the double reverse camera of the same grade was cheaper than the SLR, but now the double reverse camera has generally entered the collection field, and from the perspective of use, the cost performance is impossible to talk about.

If you buy it, the most cost-effective SLR film machine now. At that time, flagship machine Canon's EOS50E (eye-controlled focusing type), a consumer-grade SLR, can be bought in the second-hand market only around 500 yuan. If you want to pursue the effect, with a good lens and a Kodak/Fuji professional reverse film, the film will definitely be better than the top Quan Huafu SLR camera at present.