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Kamera lens

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Kamera lens
Scientific classification
Domain:Eukaryota
Kingdom:incertae sedis
Class:incertae sedis
Order:incertae sedis
Family:incertae sedis
Genus:Kamera
(O.F.Müller) Patterson & Zölffel, 1991
Species:Kamera lens
(O.F.Müller) Patterson & Zölffel, 1991
Kamera lens is a unicellular, flagellate organism and the only species of its genus Kamera. Though the species is known for centuries, it is poorly known. Its systematic position within the Eukaryota is unsure.

Anatomy, nutrition and reproduction

Kamera lens is a free-living, swimming, heterotrophic organism. The cell is small (6-7 x 2,5-3 micrometer in average [1]) and ovate, the base of its both long flagella is below the tip (subapical). A bag or rim at this place is missing. There is only one nucleus [1]. Ultrastructural characters are not known. [2]
Kamera lens lives as a saprobiont[1] and can be found in hay infusions too. William Saville Kent reported spore-masses of it in such an infusion in 1880. [3]

Taxonomy and history

The first valid description (as Monas lens) has been published by Otto Friedrich Müller in 1773 [4]. William Saville Kent placed it 1880 in the genus Heteromita [3]. Edwin Klebs moved it to Bodo in 1892, but this was rejected by H.M. Woodcock, who separated the species 1916 as Heteromastix lens in a genus of its own [1]. His insufficient description has been updated by David J. Patterson and Michael Zölffel in 1991, they named the genus Kamera, playing on words with the surviving species epithet [2]. Due lacking ultrastructural or molecularbiological data the species' rank is uncertain, thus it is placed as incertae sedis in the Eucaryota.

[edit] References

What is Photography?

ControlDescription
FocusThe adjustment to place the sharpest focus where it is desired on the subject.
ApertureAdjustment of the lens opening, measured as f-number, which controls the amount of light passing through the lens. Aperture also has an effect on depth of field and diffraction – the higher the f-number, the smaller the opening, the less light, the greater the depth of field, and the more the diffraction blur. The focal length divided by the f-number gives the effective aperture diameter.
Shutter speedAdjustment of the speed (often expressed either as fractions of seconds or as an angle, with mechanical shutters) of the shutter to control the amount of time during which the imaging medium is exposed to light for each exposure. Shutter speed may be used to control the amount of light striking the image plane; 'faster' shutter speeds (that is, those of shorter duration) decrease both the amount of light and the amount of image blurring from motion of the subject and/or camera.
White balanceOn digital cameras, electronic compensation for the color temperature associated with a given set of lighting conditions, ensuring that white light is registered as such on the imaging chip and therefore that the colors in the frame will appear natural. On mechanical, film-based cameras, this function is served by the operator's choice of film stock or with color correction filters. In addition to using white balance to register natural coloration of the image, photographers may employ white balance to aesthetic end, for example white balancing to a blue object in order to obtain a warm color temperature.
MeteringMeasurement of exposure so that highlights and shadows are exposed according to the photographer's wishes. Many modern cameras meter and set exposure automatically. Before automatic exposure, correct exposure was accomplished with the use of a separate light metering device or by the photographer's knowledge and experience of gauging correct settings. To translate the amount of light into a usable aperture and shutter speed, the meter needs to adjust for the sensitivity of the film or sensor to light. This is done by setting the "film speed" or ISO sensitivity into the meter.
ISO speedTraditionally used to "tell the camera" the film speed of the selected film on film cameras, ISO speeds are employed on modern digital cameras as an indication of the system's gain from light to numerical output and to control the automatic exposure system. The higher the ISO number the greater the film sensitivity to light, whereas with a lower ISO number, the film is less sensitive to light. A correct combination of ISO speed, aperture, and shutter speed leads to an image that is neither too dark nor too light, hence it is 'correctly exposed,' indicated by a centered meter.
Autofocus pointOn some cameras, the selection of a point in the imaging frame upon which the auto-focus system will attempt to focus. Many Single-lens reflex cameras (SLR) feature multiple auto-focus points in the viewfinder.

Many other elements of the imaging device itself may have a pronounced effect on the quality and/or aesthetic effect of a given photograph; among them are:

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