What is a dual-reflex camera?

Double-reflex camera, called double-lens mirror camera, consists of two groups of lenses with the same focal length. The upper lens usually cannot adjust the aperture and is only used for framing. The lower lens has an aperture shutter adjustment device for actual exposure.

Compared with single-lens reflex camera (SLR), dual-lens reflex camera (TLR) has one more lens for framing, and the reflector is fixed, so it does not affect framing when taking photos.

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Comparison between dual-reflex camera and SLR camera;

Dual-lens and single-lens reflex have different film specifications. 120 film is generally used for double-lens reflection, and 135 film is generally used for single-lens reflection. The previous 120 tablets were worse than 135 tablets, but the later professional 120 tablets were much better.

Double reflex is a dual-lens reflex camera, named after having a camera and a viewfinder lens respectively. Because the viewfinder and camera are two optical paths, there is parallax, so it is more common to use 120 film. SLR is a single-lens reflex camera, which uses the same lens for framing and photography, and has no parallax. 135/ 120/ all digital cameras have this structure.

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