Tài liệu Các thuật ngữ trong nhiếp ảnh pdf

Các thuật ngữ trong nhiếp ảnh Auto Exposure Bracketing: Auto Exposure Bracketing performs automatic exposure bracketing with varied shutter speed and/or aperture. Flash Exposure Bracketing: Enables a photographer to automatically bracket exposures at varied flash output levels, in TTL auto flash shooting, without changing the shutter speed and/or aperture. AE (Automatic Exposure) lock : Used to hold an automatically controlled shutter speed and/or aperture. Recommended when the photographer wants to control an exposure based on a scene's particular brightness area with Center Weighted or Spot Metering. Automatic Balanced Fill-Flash : A type of TTL auto flash operation which uses the camera's exposure meter to control ambient light exposure settings, integrated with flash exposure control. That is, flash output level is automatically compensated to balance with ambient light, resulting in a better exposure for both subject and background. Nikon's Automatic Balanced Fill-Flash system includes: 3D Multi-Sensor Balanced Fill-Flash. Multi-Sensor Balanced Fill Flash, Matrix Balanced Fill-Flash, Center-Weighted Fill-Flash and Spot Fill-Flash. 3D Multi- Sensor Balanced Fill-Flash and Multi Sensor Balanced Fill-Flash together comprise Automatic Balanced Fill-Flash with TTL Multi Sensor. Performance varies with the combination of camera body, Speedlight and lens used. Balanced fill-flash operation : A flash photography technique that balances flash illumination with the scene's ambient light. This automatic operation utilizes the some camera's Automatic Balanced Fill Flash System with TTL Multi Sensor and a compatible dedicated TTL Speedlight. Continuous Servo : AF Focus detection continues as long as shutter release button is lightly pressed and the reflex mirror is in the viewing position. Useful when the camera-to subject distance is likely to change. CPU Central Processing Unit.: The electronic component that controls an electronic product's functions. for Nikon, AF Nikkor (including D-type AF Nikkor) and Al-P-Nikkor lenses have built-in CPUs, for other camera's own terms or definitions for equivalent functions, please update me. Continuous Servo : AF Focus detection continues as long as shutter release button is lightly pressed and the reflex mirror is in the viewing position. Useful when the camera-to subject distance is likely to change. Close-Range Correction System. Most lenses are primarily designed to perform best at medium distances to infinity. When focused at extremely close distances, their image quality tends to deteriorate. This was a problem especially with large-aperture lenses having semi-symmetrical designs. To overcome this problem, Nikon invented the Close-Range Correction (CRC) System, sometimes called the "Floating Element" system. With CRC, the lens elements shift position in relation to each other, so that at close shooting distances curvature of field is reduced to the bare minimum in the case of wide-angle lenses, while spherical aberration is virtually eliminated in the Micro-Nikkor 55mm f/2.8 and the Nikkor 85mm f/1.4. The result of this ingenious design is a series of lenses which offer an increased focusing range with exceptional picture quality throughout. Ultra-Micro-Nikkor lenses: Lenses produced by Nikon for the production of IC's & LSI's. Not to be confused with the Micro-Nikkor lenses for macro photography. Some may not be producing anymore. EL-Nikkors : For photo enlargement. APO-Nikkors for photoengraving Cine Nikkor lenses for 16mm movie cameras Repro-Nikkors for 35mm life size reproduction. Depth of field : The zone of sharpest focus in front of, behind, and around the subject on which the lens is focused; can be previewed in the camera. D-type AF Nikkor lenses ( Only apply to Nikon User ): AF Nikkor lenses that send Distance Information to the F5's micro-computer. Used for 3D Color Matrix Metering or 3D Multi Sensor Balanced Fill Flash (with Nikon SB 27/SB 26/SB 25 Speedlight) . DX code : Film information code printed on film cartridge. When the camera is set to its automatic film speed setting mode and DX-coded film s loaded, it senses the film speed (common speed ISO 25 to 6400 - depends on camera models). EV Exposure Value: A number representing the available combinations of shutter speeds and apertures that give the same exposure effect under conditions of similar scene brightness and ISO. At ISO 100, the combination of a one-second shutter speed and an aperture of F1.4 is defined as EV1. The camera may be used only within the EV range of the exposure meter. For example, with the F5, the exposure metering range s from EV0 to EV20 for 3D Color Matrix Metering and Center Weighted Metering, at ISO 100 with an f/1.4 lens (Default camera used to define this term is F5, due to its advance & complex metering capabilities). Exposure bracketing : Shooting the same subject at a range of different exposures. Some camera provides Auto Exposure Bracketing/Flash Exposure Bracketing. Extra-Low Dispersion Glass All photographs are made with light, composed of many colors of the spectrum. With panchromatic black-and-white and all color films, it is essential that both blue and red light rays be brought to focus at the same plane; otherwise, color "fringing" and unsharpness will be evident. Because different wavelengths of light are bent at slightly different angles as they pass through normal optical glass, the longer the focal length of the lens, the longer the individual light rays have to travel inside the lens and the more the discrepancy in focus. While modern techniques used to correct this "chromatic aberration" are effective with normal and wideangle lenses, telephoto lenses magnify even the slightest variation in focus between the red and blue light rays, leading many photographers to assume that no long telephoto or super-telephoto lens could equal a "shorter" lens in sharpness and color correction. But Nikon overcame this obstacle by developing a new type of glass, called Extra-low Dispersion (ED) glass. Especially designed to keep red and blue in focus, ED glass produces superior color correction and has led to the creation of a whole new generation of high-performance telephoto and super-telephoto lenses. ED-series lenses are not sensitive to changes in temperature, so the problem of focus shift inherent in lenses employing calcium fluorite-crystal elements is avoided. Moreover, ED glass is hard and scratch resistant, permitting its use in exposed front and rear lens elements. Nikon's ED-series of lenses, ranging from 180mm to 1200mm, represents a major advance in photographic technology. They deliver stunning sharpness and contrast even at their large maximum apertures ED lenses are in fact so highly color-corrected that the traditional infrared focusing index is not engraved on some of them. Sharp focus extends even into the infrared wavelength range! And for the photographer used to lugging around heavy conventional telephotos ED lenses have the additional benefit of permitting the length of the lens to be reduced substantially. Nikon's Extra-low Dispersion glass is the best thing to happen to telephoto lenses since their invention. All ED Nikkor can be identified by a gold band around the lens barrel. Exposure control Programmed Auto: Camera sets both shutter speed and aperture for correct exposure. Shutter-Priority Auto: User selects shutter speed and camera sets matching lens aperture for correct exposure. Aperture-Priority Auto: User selects aperture and camera sets matching shutter speed for correct exposure. Manual: User selects both shutter speed and aperture, following or ignoring the meter's recommendations to achieve the desired exposure. Exposure compensation : Exposure compensation for available light is activated by changing the shutter speed and/or lens aperture. This is done by using AE L AF-L (Auto Exposure/Autofocus Lock) button or exposure compensation button, or by Auto Exposure Bracketing . In flash photography with a dedicated TTL Speedlights exposure compensation can also be performed by varying the amount of flash output. Camera-originated exposure compensation affects both the foreground subject and the background; variations in flash output amount affect only the foreground. Focal length : The distance from the principal point to the focal point. In 35mm-format cameras, lenses with a focal length of approx. 50mm are called normal or standard lenses. Lenses with a focal length less than approx. 35mm are called wide angle lenses, and lenses with a focal length more than approx. 85mm are called telephoto lenses. Lenses which allow the user to continuously vary the focal length without changing focus are called zoom lenses . Fill-flash : A method of flash photography that combines flash illumination and ambient light, but does not attempt to balance these two types of illumination. Flash output level compensation : A control used to adjust a TTL auto flash operation, enabling an increase or decrease of flash output to lighten or darken the flash effect. Flash shooting distance range : The distance range over which a flash can effectively provide light. Flash shooting distance range is controlled by the amount of flash output available. Each automatic Speedlight's flash output varies from maximum duration to minimum duration Close-up subjects will require lower (to minimum) output while more distant subjects will require more light up to the maximum output. The flash shooting distance range varies with the aperture, film speed, etc. Front-Curtain Sync : The flash fires an instant after the front curtain of a focal plane shutter has completed its travel across the film plane. This is the way the camera operates with the flash sync mode at Normal Sync. (See "Rear-Curtain Sync".) f-stop Useful for determining the maximum flash to-subject distance for flash photography. Flash synchronization : Timing of the flash coincides with release of the camera's shutter. There are two types of synchronization: Front-Curtain Sync, which fires the flash at the start of the exposure, and Rear-Curtain Sync, which fires the flash at the end of the exposure. Flash sync speed : Shutter speed at which the entire film frame is exposed when the flash fired in flash shooting. Most modern camera's flash sync speed is l /250 sec. or slower, some top camera model like Nikon F5, changeable to 1/300 sec. with the Custom Setting. Flexible Program : Flexible Program function temporarily shifts an automatically selected shutter speed/aperture combination while maintaining correct exposure. That is, a desired shutter speed or aperture can be selected in Programmed Auto exposure mode. Focus-Priority for autofocus : Shutter cannot be released until the subject s in focus. For situations when an in-focus subject s important. With the F5 camera body, Focus-Priority s given to Single Servo AF mode while Release-Priority is g iven to Continuous Servo AF. Using Custom Setti ing, however, you can change the priority to Release-Priority Single Servo AF or Focus-Priority Continuous Servo AF. Focus Tracking : Enables the camera to analyze the speed of the movi ing subject according to the focus data detected, and to obtain correct focus by anticipating the subject's position and driving the lens to that position&;at the exact moment of exposure. Focus Lock Built within the Nikkor AF-I and the new AF-S Nikkors. Using the cameras Continuous Servo AF operation, locking focus is a simple matter of pressing any one of the lens' four focus lock buttons, each conveniently positioned on the forward portion of the lens barrel. AF Lock is also possible from the cameras control button. Focus Range Limiter : Features that have on the Newer lenses of Nikon, the AF-I and AF-S Nikkors. Using autofocus operation, focusing time can be further reduced by setting the focusing limit switch according to the predetermined distance from the subject. Three focusing limit zones are provided. Electronic Performance and Distance Information Each lens incorporates a Central Processing Unit (CPU) which works with the automatic operation of compatible Nikon AF SLR models, as well as with each camera's light meter including Matrix, Centre-Weighted and Spot Meters. Included in each lens is Nikon's Distance Signal technology, designed to provide information about subject-to-camera distance for the Matrix Meter exposure system in Nikon AF SLR models F5, F90x, F90, F70 and F50. F-number : The numbers on the lens aperture ring and the camera's LCD that indicate the relative size of the lens aperture opening. The f-number series is a geometric progression based on changes in the size of the lens aperture, as it is opened and closed. As the scale rises. each number is multiplied by a factor of 1.4. The standard numbers for Calibration are 1.0,1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, etc., and each change results in a doubling or halving of the amount of light transmitted by the lens to the film plane. Guide number : The guide number indicates the power of a flash in relation to ISO film speed. Guide numbers are quoted in either meters or feet. ISO film speed : The international standard for representing film sensitivity. The higher the number, the greater the sensitivity, and vice versa. A film speed of ISO 200 is twice as sensitive as ISO 100, and half that of ISO 400 film. Internal Focusing. A conventional double helicoid focusing system requires that all lens groups be moved by the lens barrel to either the front or rear during focusing. This mechanism is not only complicated but bulky, more so in the case of telephoto lenses where the extra physical length of the lens requires the use of a heavier gauge metal with a consequent increase in size and weight. In [...]... does not apply any automatic flash output level compensation Flash output is controlled independently from the ambient light exposure measurement and, in most cases, illuminates a subject somewhat more strongly than with Automatic Balanced Fill Flash, making the subject stand out distinctly from the background TTL Through the-Lens: Most SLR cameras have built-in meters which measure light after it has . Các thuật ngữ trong nhiếp ảnh Auto Exposure Bracketing: Auto Exposure Bracketing performs. exposure measurement and, in most cases, illuminates a subject somewhat more strongly than with Automatic Balanced Fill Flash, making the subject stand out