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| | Rangefinder cameras are those that focus using some sort of coincident-viewing distance-determination mechanism. The most common form, as used in cameras like the [[Leica]] and other classic small 35mm cameras, is to use a prism and mirror arrangement between two viewing windows. Small adjustments in the angles of the prisms will align two superimposed images -- when the images are aligned the distance can be determined accurately by a simple mechanical cam. Such rangefinders have been used in 35mm cameras for many years and also in larger-format cameras such as "folder" medium format cameras, "Texas Leicas" like the [[Mamiya 7]] and even some early polaroid cameras. | | Rangefinder cameras are those that focus using some sort of coincident-viewing distance-determination mechanism. The most common form, as used in cameras like the [[Leica]] and other classic small 35mm cameras, is to use a prism and mirror arrangement between two viewing windows. Small adjustments in the angles of the prisms will align two superimposed images -- when the images are aligned the distance can be determined accurately by a simple mechanical cam. Such rangefinders have been used in 35mm cameras for many years and also in larger-format cameras such as "folder" medium format cameras, "Texas Leicas" like the [[Mamiya 7]] and even some early polaroid cameras. |
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| − | Other styles of rangefinder do exist, such as the electronic variety found in the [[Contax G1-G2]] cameras. In general, "rangefinder" focusing is often used to describe any focusing mechanism that doesn't view directly through the taking lens (or an identical copy of that lens, as in Twin Lens Reflex cameras). | + | Other styles of rangefinder do exist, such as t |
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| − | === Pocket and Point & Shoot cameras ===
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| − | === Single Lens Reflex ===
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| − | With a single lens reflex camera, the viewfinder image is rendered by the taking lens. In the light path is a mirror with 45° angle, that reflects the viewfinder image upwards onto a ground glass screen.
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| − | To take the image, this mirror is flipped out of the light path between lens and film plane, before the shutter opens.
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| − | The advantage of this system is, that there is no [[parallax]] error as in a [[Camera Types#Rangefinder|rangefinder]] or [[Camera Types#Twin Lens Reflex|twin lens reflex]] camera. You always see the image of the taking lens and do not need any additional viewfinders for different focal lengths. This makes the use very comfortable.
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| − | The slap of the mirror is the main problem of the SLR design, because it causes vibrations and camera shake, which makes it difficult to hand-hold an SLR at slower shutter speeds.
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| − | In many vintage SLRs (and few modern ones with interchangeable finders), the image on the ground glass is directly seen from above (waist-level finder) - it's upright, but reversed (left and right). In most modern SLRs, the ground-glass image is seen through a prism that resides on top of the ground glass screen. The view through the prism gives you an upright, unreversed viewfinder image (eye-level finder).
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| − | === Twin Lens Reflex ===
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| − | Twin Lens Reflex (TLR) cameras are "two-eyed" cameras such as the classic [[Rolleiflex]]. They consist of a ground glass on the top and two lenses on the front.
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| − | The scene viewed by the top lens (the viewing lens) is reflected by a mirror onto the ground glass. The image seen on the ground glass is back to front (left is right, right is left) which can take some getting used to.
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| − | The bottom lens (the taking lens) exposes the film. This means that, unlike [[Camera Types#Single_Lens_Reflex|Single Lens Reflex]] cameras, the viewed image is not exactly the same as the image recorded on the film - the difference being the distance between the centre of the viewing lens and the centre of the taking lens. This discrepancy is known as [[parallax]] error, which can be corrected by lifting the camera until the taking lens is as high as the viewing lens was when the image was composed.
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| − | Well-known TLR manufacturers are [[Rollei]], [[Yashica]] and [[Seagull]]. Popular and beautiful TLRs were also made by Japanese companies such as [[Minolta]] prior to the 1970's.
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