Reflex finder

Last updated

A reflex finder is a viewfinder system with a mirror placed behind a lens. The light passing through the lens is reflected by the mirror to a focusing screen, usually ground glass. The image formed on this ground glass can be observed directly, giving a waist-level reflex finder, or through a redressing optical device (set of mirrors or prism) for eye-level viewing, giving an eye-level reflex finder.

With a reflex finder, you can focus the image on the ground glass and frame your picture at the same time. It is common to find a device on the center of the ground glass to help precise focusing, for example a split-image or a microprism device. Today's reflex cameras usually incorporate autofocusing.

Reflex finders are found in:

This article was originally based on "Reflex finder" in Camerapedia, retrieved at an unknown date under the GNU Free Documentation License.

Related Research Articles

Single-lens reflex camera Camera that typically uses a mirror and prism system

A single-lens reflex camera (SLR) is a camera that typically uses a mirror and prism system that permits the photographer to view through the lens and see exactly what will be captured. With twin lens reflex and rangefinder cameras, the viewed image could be significantly different from the final image. When the shutter button is pressed on most SLRs, the mirror flips out of the light path, allowing light to pass through to the light receptor and the image to be captured.

Camera Optical device for recording images

A camera is an optical instrument used to capture an image. At their most basic, cameras are sealed boxes with a small hole that allows light in to capture an image on a light-sensitive surface. Cameras have various mechanisms to control how the light falls onto the light-sensitive surface. Lenses focus the light entering the camera, the size of the aperture can be widened or narrowed to let more or less light into the camera, and a shutter mechanism determines the amount of time the photo-sensitive surface is exposed to the light.

Digital camera Camera that captures photographs or video in digital format

A digital camera is a camera that captures photographs in digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film. While there are still dedicated digital cameras, many more cameras are now incorporated into mobile devices like smartphones, which can, among many other purposes, use their cameras to initiate live video-telephony and directly edit and upload images to others. High-end, high-definition dedicated cameras are still commonly used by professionals and those who desire to take higher-quality photographs.

View camera

In A World History of Photography, Naomi Rosenblum states that a view camera is: "A large-format camera in which the lens forms an inverted image on a ground glass screen directly at the plane of the film. The image viewed is exactly the same as the image on the film, which replaces the viewing screen during exposure." However, Rosenblum didn't give size limits for "large format"; and the book includes view camera formats smaller than 4x5, which are commonly seen as the smallest of the large format cameras.

Twin-lens reflex camera

A twin-lens reflex camera (TLR) is a type of camera with two objective lenses of the same focal length. One of the lenses is the photographic objective or "taking lens", while the other is used for the viewfinder system, which is usually viewed from above at waist level.

Wide-angle lens

In photography and cinematography, a wide-angle lens refers to a lens whose focal length is substantially smaller than the focal length of a normal lens for a given film plane. This type of lens allows more of the scene to be included in the photograph, which is useful in architectural, interior and landscape photography where the photographer may not be able to move farther from the scene to photograph it.

Stereoscopy Technique for creating or enhancing the illusion of depth in an image

Stereoscopy is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word stereoscopy derives from Greek στερεός (stereos) 'firm, solid', and σκοπέω (skopeō) 'to look, to see'. Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope.

Pentaprism

A pentaprism is a five-sided reflecting prism used to deviate a beam of light by a constant 90°, even if the entry beam is not at 90° to the prism. The beam reflects inside the prism twice, allowing the transmission of an image through a right angle without inverting it as an ordinary right-angle prism or mirror would.

Viewfinder

In photography, a viewfinder is what the photographer looks through to compose, and, in many cases, to focus the picture. Most viewfinders are separate, and suffer parallax, while the single-lens reflex camera lets the viewfinder use the main optical system. Viewfinders are used in many cameras of different types: still and movie, film, analog and digital. A zoom camera usually zooms its finder in sync with its lens, one exception being rangefinder cameras.

Ground glass Glass with roughened surface

Ground glass is glass whose surface has been ground to produce a flat but rough (matte) finish, in which the glass is in small sharp fragments.

Canon F-1 35mm single-lens reflex camera model

The Canon F-1 is a 35 mm single-lens reflex camera produced by Canon of Japan from March 1971 until the end of 1981, at which point it had been superseded by the New F-1 launched earlier that year. The Canon FD lens mount was introduced along with the F-1, but the previous Canon FL-mount lenses and older R- series lenses were also compatible with the camera with some limitations. The Canon F-1 was marketed as a competitor to the Nikon F and Nikon F2 single lens reflex cameras by Nikon.

Canon EOS RT

The Canon EOS RT is a 35mm single-lens reflex camera produced by Canon and sold from 1989 to 1992. The camera is essentially an EOS 630/EOS 600 with a pellicle mirror. Only 25,000 were manufactured at the end of the EOS 630 production run, so the EOS RT was technically "out of production" before it ever went on sale.

In the field of photography, a manual focus camera is one in which the user has to adjust the focus of the lens by hand. Before the advent of autofocus, all cameras had manually adjusted focusing; thus, the term is a retronym.

Waist-level finder

The waist-level finder (WLF), also called waist-level viewfinder (WLVF), is a type of viewfinder that can be used on twin lens and single lens reflex cameras. While it is typically found on older medium format cameras, some newer and/or 35 mm cameras have this type of finder.

Pellicle mirror

A pellicle mirror is an ultra-thin, ultra-lightweight semi-transparent mirror employed in the light path of an optical instrument, splitting the light beam into two separate beams, both of reduced light intensity. Splitting the beam allows its use for multiple purposes simultaneously. The thinness of the mirror practically eliminates beam or image doubling due to a non-coincident weak second reflection from the nominally non-reflecting surface, a problem with mirror-type beam splitters.

A director's viewfinder or director's finder is a viewfinder used by film directors and cinematographers to set the framing of a motion picture or movie camera. There are three types of director's viewfinder.

Reflector sight Optical device for aiming

A reflector sight or reflex sight is an optical sight that allows the user to look through a partially reflecting glass element and see an illuminated projection of an aiming point or some other image superimposed on the field of view. These sights work on the simple optical principle that anything at the focus of a lens or curved mirror will appear to be sitting in front of the viewer at infinity. Reflector sights employ some sort of "reflector" to allow the viewer to see the infinity image and the field of view at the same time, either by bouncing the image created by lens off a slanted glass plate, or by using a mostly clear curved glass reflector that images the reticle while the viewer looks through the reflector. Since the reticle is at infinity it stays in alignment with the device the sight is attached to regardless of the viewer's eye position, removing most of the parallax and other sighting errors found in simple sighting devices.

Afocal photography A method of photography

Afocal photography, also called afocal imaging or afocal projection is a method of photography where the camera with its lens attached is mounted over the eyepiece of another image forming system such as an optical telescope or optical microscope, with the camera lens taking the place of the human eye.

Through the Viewfinder photography

Through the Viewfinder (TtV) photography is a photographic or videographic technique in which a photograph or video or motion picture film is shot with one camera through the viewfinder of a second camera. The viewfinder thus acts as a kind of lens filter. The most popular method involves using a digital camera as the image taking camera and an intact twin-lens reflex camera (TLR) or pseudo-TLR as the "viewfinder" camera. TLRs typically have square waist-level viewfinders, with the viewfinder plane at 90 degrees to the image plane. The image in a TLR viewfinder is laterally reversed, i.e. it is a mirror image. Most photographers use a cardboard tube or similar 'contraption' to connect the two cameras. This serves to eliminate stray light and prevent reflections appearing on the viewfinder glass or on the lens of the imaging camera.

Kine Exakta The first 35mm SLR still camera

The Kine Exakta was the first 35mm single-lens reflex (SLR) still camera in regular production. It was presented by Ihagee Kamerawerk Steenbergen GmbH, Dresden at the Leipziger Frühjahrsmesse in March 1936. The Exakta name was already used by Ihagee on a roll film SLR camera line since 1933, among these the Vest Pocket Exakta Model B from which the Kine Exakta inherited its general layout and appearance. The word Kine never appeared on the camera itself, only in the instruction manuals and advertising to distinguish it from the roll film variants. Several of its features constitute the foundation for the majority of 35mm SLR cameras produced ever since, although at this stage in an infant state.