This may sound like a stupid question, but what is the difference between a reflex lens and a non reflex lens ? The reason I ask is because today a won a Bolex S-1 8mm camera from ebay, and it says it comes with a reflex lens. These cameras don't have batteries do they ? it is a wind up spring loaded camera, 1964 is the year I believe, but i hope there isn't any batteries to worry about.
thanks ...
reflex and non-reflex
Moderator: Andreas Wideroe
It's better to ask anyways. Here's a simple answer: Reflex you're seeing exactly what the lens is seeing, put your finger or hand covering the lens, and you'll see it in your viewfinder. If you don't, it's Non-Reflex, you don't see exactly what the lens see as there's a slight error which is called Parallax.
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The term reflex refers to the viewfinding system rather than the lens. It implies that the image used for viewfinding is obtained by reflecting the light around the camera at some point.
The term is often used as a synonym for "single lens reflex" (SLR), meaning that the viewing image is obtained through the same lens that forms the image on the film. This has the advantage that "what you see is what you get." In the Bolex the disadvantages are (1)the light for the viewfinding system is obtained from a beam splitter that diverts light away from the film to the viewing system. This can be overcome by using a rotating mirror shutter but this system is not used in the Bolex nor in most 8mm cameras. (2)SLR viewing ususally provides a path for unwanted light to reach the film by entering the camera through the viewfinder. This means that if the operator takes his eye away from the viewer during filming the eyepiece needs to be covered. Some cameras provide a switch to close the viewfinder.
Another reflex viewing system is the "twin lens reflex" (TLR). which uses two lenses, the viewing lens and the taking lens, that have the same focal length. The viewing system, which duplicates the taking system, is close to and parallel to the taking system. The disadvantage of TLR is that it introduces parallax error. The advantage is that no light is diverted to the viewfinder and light from the viewing system cannot reach the film. Although TLR is popular with still photographers I do not know of any TLR movie camera.
The term is often used as a synonym for "single lens reflex" (SLR), meaning that the viewing image is obtained through the same lens that forms the image on the film. This has the advantage that "what you see is what you get." In the Bolex the disadvantages are (1)the light for the viewfinding system is obtained from a beam splitter that diverts light away from the film to the viewing system. This can be overcome by using a rotating mirror shutter but this system is not used in the Bolex nor in most 8mm cameras. (2)SLR viewing ususally provides a path for unwanted light to reach the film by entering the camera through the viewfinder. This means that if the operator takes his eye away from the viewer during filming the eyepiece needs to be covered. Some cameras provide a switch to close the viewfinder.
Another reflex viewing system is the "twin lens reflex" (TLR). which uses two lenses, the viewing lens and the taking lens, that have the same focal length. The viewing system, which duplicates the taking system, is close to and parallel to the taking system. The disadvantage of TLR is that it introduces parallax error. The advantage is that no light is diverted to the viewfinder and light from the viewing system cannot reach the film. Although TLR is popular with still photographers I do not know of any TLR movie camera.
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