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Tilted Plane Focus
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. Limits to focus in imaging 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 le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
View Camera
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. This type of camera was first developed in the era of the daguerreotypeStroebel, L. D. (1986). ''View Camera Technique'', 5th ed., p. 212. Boston: Focal Press. (1840s–1850s) and is still in use today, some with various drive mechanisms for movements (rather than loosen-move-tighten), more scale markings, and/or more spirit levels. It comprises a flexible bellows that forms a light-tight seal between two adjustable ''standards'', one of which holds a lens, and the other a ground glass or a photographic film holder or a digital back.Stroebel (1986). p. 2. There are three general types, the rail camera, the field camera, and others that don't fit into either category. The bellows is a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shallow Focus
Shallow focus is a photographic and cinematographic technique incorporating a small depth of field. In shallow focus, one plane of the scene is in focus while the rest is out of focus. Shallow focus is typically used to emphasize one part of the image over another. Photographers sometimes refer to the aesthetic quality of the unfocused area(s) as bokeh. The opposite of shallow focus is deep focus, in which the entire image is in focus. Overview Shallow focus has become more popular in the 2000s and 2010s. It is also a means by which low budget filmmakers use to hide places that would require expensive props. It is often proclaimed by some to being a way to avoid the "video look." Extremely shallow focus – sometimes called ''bokeh porn'' – made its debut in cinematography in 2008 with the release of the Canon EOS 5D Mark II and the start of DSLR cinematography. Details The effect can be obtained by a larger aperture, a close viewpoint, a larger image sensor or a longer f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perspective Distortion (photography)
In photography and cinematography, perspective distortion is a warping or transformation of an object and its surrounding area that differs significantly from what the object would look like with a normal focal length, due to the relative scale of nearby and distant features. Perspective distortion is determined by the relative distances at which the image is captured and viewed, and is due to the angle of view of the image (as captured) being either wider or narrower than the angle of view at which the image is viewed, hence the apparent relative distances differing from what is expected. Related to this concept is axial magnification -- the perceived depth of objects at a given magnification. Perspective distortion takes two forms: ''extension distortion'' and ''compression distortion,'' also called ''wide-angle distortion'' and ''long-lens'' or ''telephoto distortion,'' when talking about images with the same field size. Extension or wide-angle distortion can be seen in image ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperfocal Distance
In optics and photography, hyperfocal distance is a distance beyond which all objects can be brought into an "acceptable" focus. As the hyperfocal distance is the focus distance giving the maximum depth of field, it is the most desirable distance to set the focus of a fixed-focus camera. The hyperfocal distance is entirely dependent upon what level of sharpness is considered to be acceptable. The hyperfocal distance has a property called "consecutive depths of field", where a lens focused at an object whose distance is at the hyperfocal distance ''H'' will hold a depth of field from ''H''/2 to infinity, if the lens is focused to ''H''/2, the depth of field will extend from ''H''/3 to ''H''; if the lens is then focused to ''H''/3, the depth of field will extend from ''H''/4 to ''H''/2, etc. Thomas Sutton and George Dawson first wrote about hyperfocal distance (or "focal range") in 1867. Louis Derr in 1906 may have been the first to derive a formula for hyperfocal distance. Ru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frazier Lens
The Frazier lens is a special camera lens designed by Australian photographer Jim Frazier. The Frazier lens provides an appearance of a massive depth of field 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. Factors affecting depth of field For cameras that can only focus on one object dist ..., allowing the foreground and background of an image to be in focus. Frazier's lenses have been widely used in Hollywood and wildlife cinematography. In addition to its unique depth of field properties, the Frazier lens is significantly smaller than previous deep focus lenses allowing more versatility and flexibility to cinematographers. The main feature of the lens, an extended tube with a rotating prism, allows cinematographers to place the camera in a variety of positions for a given shot. Cinematographers then rotate the prism to correct the horizon. This feature allow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth Of Focus
Depth of focus is a lens optics concept that measures the tolerance of placement of the image plane (the film plane in a camera) in relation to the lens. In a camera, depth of focus indicates the tolerance of the film's displacement within the camera and is therefore sometimes referred to as "lens-to-film tolerance". ''Depth of focus'' versus ''depth of field'' The phrase ''depth of focus'' is sometimes erroneously used to refer to the ''depth of field'' (DOF), which is the area in front of the lens in acceptable focus, whereas the true meaning of ''depth of focus'' refers to the zone behind the lens wherein the film plane or sensor is placed to produce an in-focus image. ''Depth of focus'' can have two slightly different meanings. The first is the distance over which the image plane can be displaced while a single object plane remains in acceptably sharp focus; the second is the image-side conjugate of depth of field. With the first meaning, the depth of focus is symmetrical a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth-of-field Adapter
A depth-of-field adapter (often shortened to DOF adapter) is used to achieve shallow depth of field on a video camera whose fixed lens or interchangeable lens selection is limited or economically prohibitive at providing such effect. A DOF adapter could theoretically be used on a multitude of platforms, although it is most useful on prosumer digital camcorders where high resolution is a capability but the sensor size is still small enough to elicit use of the adapter. The term 35mm adapter is common, since most designs use a focusing screen the size of a 35mm film frame (24×36 mm) and interface with lenses designed for 35mm cameras. The use of adapters has decreased largely due to the video function available on newer DSLR cameras. How it works A DOF adapter focuses an image onto a translucent screen (similar to how one would look at a focused image through a system camera's viewfinder) located between an external lens and the camera's main lens. The camcorder is able to frame th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Focus
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. Deep focus is normally achieved by choosing a small aperture. Since the aperture of a camera determines how much light enters through the lens, achieving deep focus requires a bright scene or long exposure. A wide-angle lens also makes a larger portion of the image appear sharp. It is also possible to achieve the illusion of deep focus with optical tricks (split-focus diopter) or by compositing two or more images together. The opposite of deep focus is shallow focus, in which the plane of the image that is in focus is very shallow. For example, the foreground might be in focus while the middle-ground and background are out-of-focus. When avoiding deep focus is used specifically for aesthetic effect—espe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circle Of Confusion
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, the circle of confusion is used to determine the depth of field, the part of an image that is acceptably sharp. A standard value of CoC is often associated with each image format, but the most appropriate value depends on visual acuity, viewing conditions, and the amount of enlargement. Usages in context include ''maximum permissible circle of confusion'', ''circle of confusion diameter limit'', and the ''circle of confusion criterion''. Real lenses do not focus all rays perfectly, so that even at best focus, a point is imaged as a spot rather than a point. The smallest such spot that a lens can produce is often referred to as the circle of least confusion. Two uses Two important uses of this term and conce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
