1, sensitivity (sensitivity), according to the different intensity of the light source to adjust the camera's photosensitivity.
When using a conventional camera, we can purchase different sensitivity (speed) film in response to the brightness of the shooting environment, such as the general cloudy environment available iso200, dark as the stage, the concert environment can be iso400 or higher, and digital camera There is also a similar function, which changes the iso value by changing the amplification factor of the signal amplifier in the photosensitive chip, but when raising the iso value, the amplifier also amplifies the noise in the signal to generate a coarse-grained image.
2. Aperture Aperture is a device used to control the amount of light that passes through the lens and enters the photosensitive surface inside the body. It is usually in the lens. To express the aperture size we use the f-number.
Aperture f = lens focal length / lens diameter diameter From the above formula to know that to achieve the same aperture f value, long-focus lens aperture than the short focal length lens aperture. The complete range of aperture values ​​is as follows:
F1,f1.4,f2,f2.8,f4,f5.6,f8,f11,f16,f22,f32,f44,f64
It is worth mentioning here that the smaller the f-number of the aperture, the greater the amount of light entering the same unit of time, and the amount of light entering the previous stage is just twice that of the next stage, for example, the aperture is adjusted from f8 to f5.6, The amount of light is doubled, and we also say that the aperture has opened a big one. For consumer digital cameras, the aperture f value is often between f2.8-f16. In addition, many digital cameras can make 1/3-level adjustments when adjusting the aperture.
3, In addition to the aperture and shutter priority level above the digital camera in addition to automatic mode, there will usually be aperture priority (shutter priority), shutter priority (shutter priority) two options, so that you can first in some occasions Decide on a certain aperture value or a certain shutter value, and then use the appropriate shutter or aperture, respectively, to present different depth of field (sharpness) or effect of the picture.
4. Aperture-Priority Exposure Mode After we determine the f-number of the aperture first, the camera's light metering system automatically selects the appropriate shutter speed (accurately without segment-type shutter speed) according to the current light conditions. A digital camera with an exposure mode dial usually engraves the 'a' letter on the turntable to represent the aperture priority mode (see Figure 4). The aperture-priority mode is suitable for photography focusing on depth of field effects.
Since the focal length of a digital camera is much shorter than that of a conventional camera and the aperture of the lens is small, it is difficult to produce a narrow depth of field. Some digital cameras have a special portrait exposure mode that uses built-in programs to blur the foreground and background.
When using a conventional camera, we can purchase different sensitivity (speed) film in response to the brightness of the shooting environment, such as the general cloudy environment available iso200, dark as the stage, the concert environment can be iso400 or higher, and digital camera There is also a similar function, which changes the iso value by changing the amplification factor of the signal amplifier in the photosensitive chip, but when raising the iso value, the amplifier also amplifies the noise in the signal to generate a coarse-grained image.
2. Aperture Aperture is a device used to control the amount of light that passes through the lens and enters the photosensitive surface inside the body. It is usually in the lens. To express the aperture size we use the f-number.
Aperture f = lens focal length / lens diameter diameter From the above formula to know that to achieve the same aperture f value, long-focus lens aperture than the short focal length lens aperture. The complete range of aperture values ​​is as follows:
F1,f1.4,f2,f2.8,f4,f5.6,f8,f11,f16,f22,f32,f44,f64
It is worth mentioning here that the smaller the f-number of the aperture, the greater the amount of light entering the same unit of time, and the amount of light entering the previous stage is just twice that of the next stage, for example, the aperture is adjusted from f8 to f5.6, The amount of light is doubled, and we also say that the aperture has opened a big one. For consumer digital cameras, the aperture f value is often between f2.8-f16. In addition, many digital cameras can make 1/3-level adjustments when adjusting the aperture.
3, In addition to the aperture and shutter priority level above the digital camera in addition to automatic mode, there will usually be aperture priority (shutter priority), shutter priority (shutter priority) two options, so that you can first in some occasions Decide on a certain aperture value or a certain shutter value, and then use the appropriate shutter or aperture, respectively, to present different depth of field (sharpness) or effect of the picture.
4. Aperture-Priority Exposure Mode After we determine the f-number of the aperture first, the camera's light metering system automatically selects the appropriate shutter speed (accurately without segment-type shutter speed) according to the current light conditions. A digital camera with an exposure mode dial usually engraves the 'a' letter on the turntable to represent the aperture priority mode (see Figure 4). The aperture-priority mode is suitable for photography focusing on depth of field effects.
Since the focal length of a digital camera is much shorter than that of a conventional camera and the aperture of the lens is small, it is difficult to produce a narrow depth of field. Some digital cameras have a special portrait exposure mode that uses built-in programs to blur the foreground and background.
Thermal Relay is used to protect AC three-phase asynchronous motor/electric motor against overload and open phase. Korlen electrical appliances produce thermal relay switch in wholesale,being a good thermal overload relay suppliers from china. We also offers Manual Motor Startor , AC Contactor, LED Light, Circuit Breaker etc.
Thermal Relay
Thermal Relay,Latching Relay,Reed Relay,Polarized Relay
Wenzhou Korlen Electric Appliances Co., Ltd. , http://www.korlenelectric.com