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Tilted plane photography is a method of employing focus as a descriptive, narrative or symbolic artistic device. It is distinct from the more simple uses of selective focus which highlight or emphasise a single point in an image, create an atmospheric bokeh, or miniaturise an obliquely-viewed landscape. In this method the photographer is consciously using the camera to focus on several points in the image at once while de-focussing others, thus making conceptual connections between these points.
Focus is relative to spatial depth. Selective focus in photography is usually associated with depth of field. A pinhole camera generates an image of infinite relative focus, from a point just outside the camera opening out to infinity. Lenses focus more selectively so that, for objects near the lens, the distance between lens and sensor or film is increased and is shortened for more distant objects, to a point beyond which all is in focus. In telephoto lenses this point may be tens or hundreds of metres from the camera. Wide-angle lenses distinguish differences in depth only up to a short distance, beyond which all is in focus.
Depth of field is an effect that permits bringing objects into focus at varying distances from the camera, and at varying depth between each other, into the field of view. A short lens, as explained above, will bring objects into focus that are relatively close to the camera, but it will also keep focus at greater distances between objects. A telephoto lens will be very shallow in its gamut of focus.
Reducing the size of the aperture of the lens deepens the focus. At a pinhole size this will increase in effect, though the closer the objects are to the camera, the shorter the distance between focussed objects.
Because focus depends on the distance between lens and the sensor or film plane, focus in the space in front of the camera is not on a point but rather on a plane parallel to the film plane. [1] Spherical construction of lenses, rather than the ideal parabolic construction which is rarely and expensively achieved, means that this plane is slightly concave—more so in simple single element lenses and increasingly so with lenses of lower quality construction and materials. Compound lenses are built to correct this "spherical aberration" or "curvature of field".
Varying the distance between the lens and sensor or film plane across the field of view permits focussing on objects at varying distances from the camera. One means of achieving this is to tilt the lens and/or the sensor or film plane in relation to each other. This will mean that individual points in the picture plane will focus on different points of depth, with the effect that the plane of sharp focus will tilt.
This technique is based on the principle of Scheimpflug which, traditionally, is combined with small aperture to increase the gamut of focus beyond that achievable by depth of field alone. Usually no out-of-focus artifacts are desired in the image resulting from Scheimpflug adjustments. Here the converse is true. With the lens at full aperture, the photographer selects points in depth in the scene on which to focus and throws other points out-of-focus. This increases the contrast between the sharp and blurred areas and the selected application of focus and blur remains apparent to the viewer.
A view camera permits full, incrementally calibrated control over this technique, though it is possible to achieve with other cameras and formats. It is possible to achieve similar effects on a 35mm camera or digital single-lens reflex camera (DSLR) using a special tilt-shift lens, or by manually holding a lens that is removed from its mount.
Julia Margaret Cameron was a strong advocate of this use of selective focus. For example, in "Prayer and Praise", produced in 1865, there is a deliberate placement of focus at more than three points: on the face and parts of the body of the foreground child; and faces of mother and father; while a second child's face is thrown radically out of focus. [N 1]
The depth of field (DOF) is the distance between the nearest and the furthest objects that are in acceptably sharp focus in an image captured with a camera.
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane.
A view camera is a large-format camera in which the lens forms an inverted image on a ground-glass screen directly at the film plane. The image is viewed and then the glass screen is replaced with the film, and thus the film is exposed to exactly the same image as was seen on the screen.
In optics, a circle of confusion (CoC) is an optical spot caused by a cone of light rays from a lens not coming to a perfect focus when imaging a point source. It is also known as disk of confusion, circle of indistinctness, blur circle, or blur spot.
In photography, bokeh is the aesthetic quality of the blur produced in out-of-focus parts of an image. Bokeh has also been defined as "the way the lens renders out-of-focus points of light". Differences in lens aberrations and aperture shape cause very different bokeh effects. Some lens designs blur the image in a way that is pleasing to the eye, while others produce distracting or unpleasant blurring. Photographers may deliberately use a shallow focus technique to create images with prominent out-of-focus regions, accentuating their lens's bokeh.
A camera lens is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.
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.
Macro photography is extreme close-up photography, usually of very small subjects and living organisms like insects, in which the size of the subject in the photograph is greater than life size . By the original definition, a macro photograph is one in which the size of the subject on the negative or image sensor is life size or greater. In some senses, however, it refers to a finished photograph of a subject that is greater than life size.
The Scheimpflug principle is a description of the geometric relationship between the orientation of the plane of focus, the lens plane, and the image plane of an optical system when the lens plane is not parallel to the image plane. It is applicable to the use of some camera movements on a view camera. It is also the principle used in corneal pachymetry, the mapping of corneal topography, done prior to refractive eye surgery such as LASIK, and used for early detection of keratoconus. The principle is named after Austrian army Captain Theodor Scheimpflug, who used it in devising a systematic method and apparatus for correcting perspective distortion in aerial photographs, although Captain Scheimpflug himself credits Jules Carpentier with the rule, thus making it an example of Stigler's law of eponymy.
The science of photography is the use of chemistry and physics in all aspects of photography. This applies to the camera, its lenses, physical operation of the camera, electronic camera internals, and the process of developing film in order to take and develop pictures properly.
Deep focus is a photographic and cinematographic technique using a large depth of field. Depth of field is the front-to-back range of focus in an image, or how much of it appears sharp and clear. In deep focus, the foreground, middle ground, and background are all in focus.
Lensbaby is a line of camera lenses for DSLR and mirrorless cameras that combine a simple lens with a bellows or ball and socket mechanism for use in special-effect photography. A lensbaby can give effects normally associated with view cameras. The lenses are for use in selective focus photography and bokeh effects.
Tilt–shift photography is the use of camera movements that change the orientation or position of the lens with respect to the film or image sensor on cameras.
A photographic lens for which the focus is not adjustable is called a fixed-focus lens or sometimes focus-free. The focus is set at the time of lens design, and remains fixed. It is usually set to the hyperfocal distance, so that the depth of field ranges all the way down from half that distance to infinity, which is acceptable for most cameras used for capturing images of humans or objects larger than a meter.
Miniature faking, also known as diorama effect or diorama illusion, is a process in which a photograph of a life-size location or object is made to look like a photograph of a miniature scale model. Blurring parts of the photo simulates the shallow depth of field normally encountered in close-up photography, making the scene seem much smaller than it actually is; the blurring can be done either optically when the photograph is taken, or by digital postprocessing. Many diorama effect photographs are taken from a high angle to simulate the effect of looking down on a miniature. Tilt–shift photography is also associated with miniature faking.
Sports photography refers to the genre of photography that covers all types of sports.
An ultra wide-angle lens is a lens whose focal length is shorter than that of an average wide-angle lens, providing an even wider view. The term denotes a different range of lenses, relative to the size of the sensor in the camera in question.
The Micro Four Thirds system is a standard released by Olympus and Panasonic in 2008, for the design and development of mirrorless interchangeable lens digital cameras, camcorders and lenses. Camera bodies are available from Blackmagic, DJI, JVC, Kodak, Olympus, Panasonic, Sharp, and Xiaomi. MFT lenses are produced by Cosina Voigtländer, DJI, Kowa, Kodak, Mitakon, Olympus, Panasonic, Samyang, Sharp, Sigma, SLR Magic, Tamron, Tokina, TTArtisan, Veydra, Xiaomi, Laowa, Yongnuo, Zonlai, Lensbaby, Kowa, Venus Optics and 7artisans amongst others.
In photography, a long-focus lens is a camera lens which has a focal length that is longer than the diagonal measure of the film or sensor that receives its image. It is used to make distant objects appear magnified with magnification increasing as longer focal length lenses are used. A long-focus lens is one of three basic photographic lens types classified by relative focal length, the other two being a normal lens and a wide-angle lens. As with other types of camera lenses, the focal length is usually expressed in a millimeter value written on the lens, for example: a 500 mm lens. The most common type of long-focus lens is the telephoto lens, which incorporate a special lens group known as a telephoto group to make the physical length of the lens shorter than the focal length.
The Brenizer Method, sometimes referred to as Bokeh Panorama or Bokehrama, is a photographic technique characterized by the creation of a digital image exhibiting a shallow depth of field in tandem with a wide angle of view. Created by use of panoramic stitching techniques applied to portraiture, it was popularized by photographer Ryan Brenizer.