Using LED glowsticks, flashlights, even fireworks, combined with time-lapse photography, light graffiti artists create a unique tagging that wraps around objects dimensionally, allowing them to tag in a way they'd never be able to with spraypaint. Very cool!
here more on light painting and light graffiti
Often beginning photographers may hear or meet in the text mysterious words, the sense of which is clear only to professional photographers. Without comprehension of such "magic" words it is difficult to read the special literature dedicated to the photo details, to communicate with the photographers, to participate in forums, and in general to run in the photo business. Here is a glossary of the main photo terms which are necessary to be understood, if you want to make a photo.
Adapter lens
Positive or negative lenses mounted on a lens for a focal distance change. Positive lenses reduce general focal distance, negative, increase, accordingly. They are marked in diopters.
Maximum definition
The largest image (in pixels), which can be obtained by a photographic camera.
"Fish-eye lens"
Version of a wide-angle viewer, the viewing angle of which is 180_ or more. The viewing angle imitates vision of a fish. The picture has a strong barrel-type distortion. Such lenses are applied with the purpose to receive special art effect.
Volume range
Matrix or film capability to image set of colors and brightness of the most light and most dark areas of the picture.
Mega pixels
The more number of mega pixels, the greater size of a photo you can print. The number of effective megapixels is more significant, than their total number, as the image is formed by effective pixels.
Test Pattern
From fr. mira, mirer - to esteem on light, to take aim at something. A special test defines a picture quality at testing. So lenses are tested, for example. The test pattern is a plate or paper with the marked figure. There are radial and shaped patterns. The resolving power of a lens is determined by reproduction of shaped or radial patterns on the picture.
Soft-focus lens
The lens creating the softened pictures with reduced contrast at the expense of sharpness reduction. "Softening" of an image contrast is conditioned by residual lens aberrations or with the help of nozzles ensuring) sharpness reduction of the picture. As nozzles may be used small-sized grids, "diffusive" optic nozzles.
Normal lens
The lens is considered normal ("nominal"), if the frame diagonal is approximately equal to a lens focal distance For 35mm cameras it is a lens with focal distance of 50 mms.
Optical wedge
Phenomenon, when all colors in the picture are mixed without visible transitions and gradations. The optical wedge is considered as the golden standard of the photo realistic picture.
Parallax
The effect of frame borders convergence which is defined through the view finder, and frame which is formed by a lens on a matrix. The parallax arises owing to an optical range finder axis convergence of an axis and of a camera lens. The effect of a parallax is especially visible at close up filming and at macro filming.
Pentaprism
A pentagonal glass prism used in view finders of reflex cameras. Gives direct, not reversed image of object of filming.
Perspective
Depending on a lens focal distance the long shot objects can appear closer or further from object of filming. This visual effect is called as a perspective. The wide-angle viewers, , visually augment spacing interval between object and background, as a rule, because of that it seems, that the objects of a background are further from filmed object, than actually they are. The telelenses reduce spacing interval between object of filming and background, because of that the objects of a background seem closer, than actually they are. The wide-angle viewers are used, when it is necessary to show an object of filming, and a background, the telelenses accentuate an object of filming only.
Cushion-like distortion
Owing to not ideal design of a lens there is a distortion of the picture. Usually this effect arises at filming by a wide-angle viewer. On the picture the horizontal and the vertical lines are concaved to the frame center.
Lead
This is a special method of filming of a mobile object with the purpose to receive a snapshot, which underlines motion. The object is sharp on a blurred background. The filming with lead is usually carried with a rather long exposure. The camera is continuously displaced after motion of an object.
Blooming
The optical blooming reduces a reflection coefficient of lenses surfaces. Nonabsorbing films are put on them on which the depth is commensurable with an optical radiation wavelength. Without them the reflection loss of light can reach 10 percents from irradiance. And in a lens with large number of surfaces - up to 70 percents. The multiple reflection from refracting surfaces results in an indirect illumination appearance inside of a lens that degrades picture quality. In the basis of the blooming process lies the light interference reflected from forward and back borders of a film. The reflected light waves are mutually discharged and the intensity of a transmitted light strengthens.
Raster
From a German word "raster", from Latin - rastrum: "raker", "mattock". Special grids with lines frequency from 20 up to 100 on 1 cm used in polygraphs at the half-tone originals reproduction. The raster is applied for obtaining of the stereoscopic pictures.
Resolution of lens
The property of a photographic lens to transmit on the optical picture small-sized parts separately is measured in lines on mm.
Super wide-angle objective
The lens has a viewing angle more than 90_ that corresponds to the focal distance of 24 mms (for 35mm cameras).
Illumination
Maximum aperture rating at the given focal distance.
Photo sensibility
Numerical value of general photo sensibility. Expressed in terms of ISO (international standard). At transition from one number of photo sensibility to another the exposure varies in inverse proportion to numbers of photo sensibility.
Synchronization with a flash
The minimum time of a full shutter opening, which is necessary that is enough expose a frame, which is filmed with a flash.
The stabilizer.
At filming with long exposition there is a danger of a blurring effect when the photographic camera is not fixed on the rigid basis. To remove the blurring effect the photographic cameras producers use optical stabilization (IS - for Canon, VR - for Nikon, O.I.S. - for Panasonic, OS for Sigma), in which fixity of the projected picture on a photosensitive stuff of a photographic camera is provided with a mobile member of an optical system. The systems AntiShake (Konica Minolta) and Super Steady Shot (Sony) are based on a matrix shift principle of operation same, as for other systems, but lens element doesn't move but sensor does. The advantage of such system that it works with any lenses.
Stop
Stage of an exposition. It means a difference between two adjacent values for the aperture: for example, between f/4 and f/5,6. If it is a question of exposure, the time changes twice. Stop means, that quantity of light, which falls on a light sensor, varies twice.
Spherical aberration
Blur of the picture, caused by that the light beams passing through a lens on different spacing intervals from an axis of sighting, have incompatible focuses.
Lens
Lens permitting to shoot remote subjects with larger, than for customary lenses, magnification. This concept is used instead of "a long-focus lens", meaning a lens with focal distance larger, than a diagonal of frame.
Field vision angle
The focal distance determines a zone of the picture, which is projected on a matrix or film. The field vision angle
depends on focal distance of a lens and is measured in grades. The more focal distance of a lens is, the less angle its field of vision.
Fix-focus
Or fix-focal - type of lenses, which focal distance is permanent. They do not allow to bring near or to move away an object of filming concerning a given focal distance. More often these are changeable lenses for reflex cameras.
Fixed focus
It is usually set on infinite distance. It is built into cheap cameras. Such camera theoretically should transmit all short-shot and long-shot objects equally sharply. Such lens does not give a capability to treat filming creatively.
Focal plane
Plane, perpendicular to the axis of an optical lens system.
Focus
From lat. focus - "locus", " fire"). A point, in which the parallel light beams, having passed through an optical system, intercepts.
Focal distance
Spacing interval from a plane of a matrix or film (focal plane) up to a main back optical plane of a lens at its focusing at infinity. Depending on focal distance the lenses are subdivided on wide-angle, normal and telelenses.
Chromatic aberrations
From greec. chroma - "colour", "paint". This kind of distortion is conditioned by relation of refractive index of transparent mediums (glass) to a light wavelength, passing through them. On the picture of contrast objects there are violet halations. The chromatic aberrations are patched by achromatic optical systems. Chromatic colour
All colours, except for black, white and grey, belong to achromatic colour. Chromatic colours differ on hue, luminosity and saturation.
Color temperature
Grades on a Kelvin scale, which measure the color component of light.
Camera vibration
Chatter, vibration of the camera, which reduces the sharpness of a snapshot or makes it blurred. The more exposition period, the more probability of vibration appears. It can be caused by arms' trembling of the photographer, sharp clicking the push button or by clap of a mirror in reflex cameras etc. To avoid this effect it is necessary to use a mount and make a release with the help of the console or automatic releaser.
Noise
The arbitrary color point deviation. A set of color impregnations appear on the picture. The more the noise, the more the matrix sensitivity is and the longer the exposure is.
Exposition volume
EV means value of an exposition: exposure and aperture. EV 0 corresponds to per 1 second exposure and aperture f/1.0. When EV changes per unit the exposition varies on one stage.
Exposition metering
The metering system of a photometric light intensity of object of filming. It is necessary for precise definition of scene exposition. Exposition metering may be matrix, multispot, spot, integral, partial and centre-weighted.
Exposition
Quantity of light, which falls on a light sensor (matrix, film). It is determined by product of illuminating intensity on time of illumination. The quality of a snapshot - underexposure or overexposure depends on an exposition. If the snapshot is too dark it is underexposed, that means matrix has got not enough light. If the snapshot too light it is overdone, that means matrix has got a lot of light.
Exposure compensation
The input of the exposition corrections which automatic exposure correction of the camera has set. It is applied in composite light conditions, and also for obtaining off-gauge results.
Exposure meter
The device for value definition of exposure meter parameters at photography.
Exposure pair
Combination of exposure and aperture, which determines an exposition. Has a principle of transposability - exposition is saved at transition from one exposure pair to another. If one of parameters is increased second is accordingly decreased.
Aberration
From lat. aberratio - evading. Aberration is distortion, which is created by optics because of an imperfection of reflecting and refracting surfaces of an optical system. The aberration expresses that the picture receives indistinct, with incorrect transfer of object geometry or it is coloured, for example, contoured.
Auto focus
The system of an auto focus in digital cameras may be passive or combined. In a foreground the camera calculates spacing interval up to filmed object and focalizes a lens on this spacing interval. In a mode of a passive auto focusing the electronics engineering studies the picture searching contrast lines and objects borders. Then the camera is focalized so that these lines of were maximum sharp.
Anastigmat
From greec. an - "¬´not", "¬´without" and "¬´astigmatism". It is a lens, in which the special lenses correcting aberrations are used.
The aperture
From lat. aperture - foramen. It is value, which means a foramen of an optical system (lens) used at the moment of filming. The aperture of a lens determines quantity of light, which passes through a lens, and a resolution of lens.
Apochromat
From greec. apo - "¬´from", "¬´from", "¬´without" and chroma - "¬´colour", "¬´paint". It is a lens, for which the chromatic aberration for three and more colours is corrected. For example, for violet, green and red. The lens from a special glass are used in a lens, the mirrors are entered in an optical system, optics design is complicated.
Artefacts
Distortions introduced into the picture by a photographic camera. The part of the information at JPEG file compression is lost, there are distortions which appear as "variegations" - artefacts. The artefacts can be added by inaccuracy of image processing by the camera, deterioration of matrix properties, electronic noise etc.
Astigmatism
From greec. A - "¬´not", "¬´without", and strigme - "¬´point". The type of aberration of an optical system, which is expressed by that the points are not arranged on a principal axis of an optical system and they are figured by two orthogonally related sections arranged apart from each other. Owing to astigmatism the picture may be indistinct. It may be corrected by usage of lenses of different curvature, which have different refractive indexes. Thus the astigmatism of one lens is compensated by astigmatism of another one.
Nonspherical optics
From greec. A - "¬´not", "¬´without" and sphaira - "¬´sphere". Production of optical with nonspherical surfaces allows to create optical systems with the improved correction of aberrations. The elements with a nonspherical surface have the asheric form: an ellipse, barrel, and parabola. They are obtained by deposition on a spherical surface of transparent or reflecting material variable on a bed depth.
Achromat
From greec. achromatos - "¬´colourless". It is a lens, for which the chromatic aberrations for two colours are corrected. For example, for violet and yellow. The spherical aberration is partially removed. It is used as soft-focus lens.
Achromatic colours
Grey colour of not luminous objects, which have no chromaticity. They differ only in luminosity. From the lightest - white up to darkest- black, which are absent in a visible spectrum. In process of luminosity increase they form a grey scale. The scale with constant value of an absorbency difference of two adjacent fields will be used for quality control of photographic stuffs and processes.
Analog-digital converter
The microcircuit, which is used in a photographic camera. It is intended for a picture conversion, obtained from a matrix, to a digital data format, which can be used in the computer.
Bayonet
Bayonet coupling. The removable lens connector for attachment to a body of the camera. All leading producers of cameras have their own standard bayonet, which is not conformant to production of other corporations.
White balance
Regulation of tint of white colour in the picture. The different light sources give white colour different tints. The system of white balance control in the camera removes tints intrinsic to different light sources.
Blend
A special nozzle on a lens which removes an undesirable flare, excepting a dazzle of a light beam on the picture. It is produced from plastic, metal, gum in the form of rings - truncated cone or four-leaved pyramid with a black mat inside.
Barrel-type distortion
The image distortion, which arises owing to of a design imperfection of a lens - Horizontal and the vertical lines of the picture are curved to frame boundaries. Arises at filming by a wide-angle viewer.
Bracketing
Filming by the camera of a series of frames (three or more), which differ in parameters with a given interval of values (exposition, white balance etc.), with the purpose to select optimal a snapshot. At bracketing on an exposition one snapshot will be dark, other light, third normal. Such filming is applied in composite conditions, when the parameters are selected by practical consideration. The snapshots can be combined in the photoeditor for a ratio increase between light and shade, volume dynamic range expansion.
Vignetting
From fr. vignette - "headband". Partial black-out of beam of light passing through a lens, inclined in relation to a sighting axis. As the result the image illumination drops step-by-step from centre to boundaries at transition. The cause may be both a lens design, and additional supplementary lenses for blend.
Exposure
The time interval during which light falls on a matrix or film. It is provided at the expense of the shutter, and exposure definition means time, during which the shutter opens. The exposure depends on illuminating intensity of object of filming, sensitivity of a matrix (film) and established aperture. To calculate her (it is possible under the special table, exposure meter. In modern cameras the automatics of the camera manages such calculus independently.
High key
The special representational method with the help of which a tender on gradation is formed, almost air and mild photo consisting from "¬´white" with very light grey tones practically.
Hypofocal distance
Spacing interval from a matrix (film) plane up to a subject, at a focusing on which back border is of sharply figured space is in perpetuity. It depends on focal distance established by aperture, physical sizes of the sensor and film format.
Histogram
The chart demonstrating of the picture tones distribution. The grey scale of tones imaged in horizontal direction: from white up to black. And on a vertical axis the number of pixels of given brightness on the picture is demonstrated. The histogram allows setting an exposition precisely.
Image depth resolution
Spacing interval along an optical axis between two planes of objects in space, within the limits of which they are transmitted enough sharply on a photo. At a lens focusing on a subject arranged on a hypofocal distance, back border of sharply figured space is in perpetuity.
Depth resolution
Spacing interval along an optical axis in picture space, within the limits of which the optical picture formed by a lens, has sufficient sharpness. At a focusing of object a part of space appears behind object and before it. “Depth of resolution” also concerns to this space. It is increased if to shut the aperture, and decreases if to uncover the aperture. At the invariable aperture the depth of resolution is less, the less is a distance on which a lens is focalized, and it is more, the longer distance of filming is. The depth of field depends on focal distance of a lens: at identical values of the aperture and distance up to object, the more depth of resolution will be for lenses with smaller focal distances (wide-angle) and less for lenses with large focal distances (telelenses). The small aperture numbers are for filming portraits, scenes, for which central object should be in focus only, and remaining part of frame is blurred. The large aperture numbers are for photos, on which everything should be in focus - landscapes, snapshots formation.
Hot shoe
The metallic connector on a body of the camera for the external removable flash installation.
The aperture
From greec. diaphragma - "¬´partition"(¬´dividing wall"). The aperture allows changing a foramen limiting luminous flux section diameter which passes through a lens. Depth of resolution depends on the aperture, accordingly at cover of the aperture the exposure is increased. The aperture can be controlled manually, and by automatics of the camera.
Aperture number
The value of the aperture, established on a lens, is called as aperture number. It is a value, inverse to an angular aperture lens value. This parameter, as well as exposure, is determined at filming. The aperture number is equal to relation of lens focal distance to maximum diameter of its entrance pupil. The values are put on a lens carriage. The scale of aperture numbers is constructed by a principle of a scale of photosensibility: at transition from one value to other - adjacent, diameter of a foramen is decreased approximately in 1,4 times. At change of aperture number on one point light quantity, which passes through a lens, changes twice. The more aperture number is the less focal aperture of the lens aperture which lets light less twice to pass through contrasted to the previous value. And on the contrary - the less aperture number is, the more focal aperture of the lens aperture will let light to pass through contrasted to the previous value A unified international values of angular apertures of a lens series is adopted as a matter of convenience. The aperture number - also a lens speed measure, it influences speed and accuracy of an auto focusing, on capacity to shoot in conditions of poor illumination. The less aperture F number is the more diameters of a lens opening and the more light falls on a matrix of the camera. The standard values F make series: 1,0, 1,4, 2, 2, 8, 4, 5,6, 8, 11, 16, 22, 32.
Distortion
Geometrical image error, which lens produces because of its imperfection. The distortion may be a barrel-type (with the curved boundaries) and cushion-like (with concaved edges boundaries)
Image graininess
Dissimilarity of blackening of developed photolayer segment. Characteristically on the picture, this is obtained on halogen-silver photographic material. The graininess degrades picture quality, but it is used for obtaining art effects also.
Zoom
The zooming (increase of object of filming) may be optical and digital. The picture quality at usage optical zoom is incomparably better. Digital zoom is same, as well as at computerising. Digital zoom it is better not to use in the camera.
Zoom-lens.
Zoom lens with a varying focus distance.
Interpolation
Some cameras are equipped with an interpolation function. It allows adding additional pixels to the existing picture for increase of its size. There are some algorithms of new pixels attachment with the brightness and colour analysis surrounding the adjacent: bilinear and bicubic.
Kit
In a title of the goods the word Kit is usually added, if the goods are delivered in an amplate complete set (with an additional lens, jacket, memory card etc.).
Ring-type flash
The photo flash in the shape of a ring, which is placed around of a camera lens. It creates almost shadow-free illumination it is applied at macro filming.
Contour light
The light directed in a lens close to its optical axis. As the result of this operation light contour on lighted object at a completely shaded its frontal plane.
Zoom ratio
Lens focal distance change ratio it is equal to a maximum focal distance of a lens to its minimum focal distance (mm) relation.
The light filter Ratio
This value means how much it is necessary to increase exposure at filming with the light filter as contrasted to by exposure under the same conditions without it. Depends on the light filter characteristics, spectral sensibility of a photosensitive material and spectral light content.
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Blur circle
Distorted image of a point, which a lens produces. At spatial object filming it is impossible to receive the picture of points, which lie on different spacing intervals from taking object equally sharply. At the distance of best vision (250-300 mms) on the printed photo the blur circle is accepted by the person as a point, if its diameter is no more than 0,1 mms.
The shutter
The device of photographic cameras permitting to regulate time of exposition.
Long-focus lens
The lens, focal distance of which is more than in 1,5 times surpasses a diagonal of a frame (picture field). The long-focus lens allows receiving large-scale snapshots of remote objects.
Adobe announced the release of Adobe Photoshop Elements 5.0, if you missed it here’s the info. The new version of its software for photograph retouching. Certainly, as any new version of the program, Photoshop Elements 5.0 offers new functions. The latest of them are oriented towards photographs sharing particularly. Here is a brief list of what the new version will offer:
* the possibility of creating animated photo galleries, especially owing to the Flash technology;
* the possibility of transferring easily photographs or/and animations on the web without leaving the software;
* the possibility of ordering the editions of photographs directly from the software;
* compatibility with a cellular phone or pocket computers;
* the possibility of transferring rapidly photographs towards the peripheral device mentioned above;
* the new retouching tools (wrinkles rubber, automatic correction of color spectrum, brightness and contrast.
Moreover, supporting the manipulations of files of RAW type (considered as being the best in terms of the quality of images), Photoshop Elements 5.0 offers the folioscope function. This permits you to transform a sequel of photos into a series of animations that gives the effect of movement.
Adobe Photoshop Elements 5.0 will be available in the beginning of October for $70 all taxes included.
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