88 Glossary that gives you a full understanding of digital camera

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88 Glossary that gives you a full understanding of digital camera Font [big, medium, and small] color [blue, green, and black]
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1. AE lock

AE is the abbreviation of Automatic Exposure Control device for automatic exposure, and the AE lock is locked in an AE setting. It is used to manually control the exposure volume during Automatic Exposure to ensure normal exposure of the subject.
Note the following points when using the AE lock: 1. Automatic Exposure (AE) Lock cannot be used in manual or self-timer mode. 2. Do not adjust the aperture size after pressing the auto-exposure lock. 3. Do not use the (AE) lock when using a flashlight for photography.

2. CCD

Charged coupled device is a circuit device that senses light, just like a negative film of a traditional camera, you can think of it as a tiny sensor particle that is filled at the rear of an optical lens. When light and image pass through and are projected to the CCD surface from the lens, the CCD will generate current, convert the inductive content into digital data for storage. The larger the number of CCD pixels and the larger the size of a single pixel, the clearer the collected image. Therefore, although the number of CCD is not the only key to determining the image quality, we can regard it as one of the important criteria for determining the camera level.

3. CMOS

Comple-mentary metal-oxicle-semiconductor, translated as "complementary metal oxide semiconductor"

4. dpof

Dpof refers to a digital printing sequence command used to record information on storage media (image and memory cards. In this format, you can set the number of images taken by a digital camera to be printed.

5. EXIF

The so-called EXIF (exchangerable image file format for digital still cameras) is by jeita (Electronic Information Technology Industry Association) specifications of the method used to specify additional information on JPEG images and audio files.

6. exif2.2

EXIF 2.2 is a new digital camera file format that contains a variety of shooting information required for optimal printing.

7. PTP

PTP is short for "picture Transfer Protocol.

PTP is a standard first developed by Kodak and Microsoft through consultation. Image devices that comply with this standard can be better shared by systems and applications after being connected to Windows XP, especially in terms of network transmission, the system can directly access these devices to upload images during network album creation, and transfer images during online chats.

Of course, this is mainly for the convenience of ordinary users with little computer knowledge, so that cameras, application software, websites... together, it is easier to complete some silly functions.

8. Tiff format

Tiff is a flexible image format. Its full name is tagged image file format. The file extension is TIF or tiff. This format supports 256 colors, 24-bit true color, 32-bit color, 48-bit color, and other color bits. It also supports multiple color modes such as RGB, CMYK, and YCbCr, and supports multiple platforms. TIFF files can be non-compressed, large or compressed, and support multiple compression methods, such as raw, RLE, LZW, JPEG, ccitt3, and 4 groups.

9. Wave

This is the standard Windows file format used for recording. The file extension is "WAV" and the data format is PCM or compressed.

10. Image Transmission Protocol

Picture transfer protocol is short for PTP. PTP is a standard developed by Kodak and Microsoft through negotiation. Image devices that comply with this standard can be better shared by systems and applications after being connected to Windows XP, especially in terms of network transmission, the system can directly access these devices to upload images and transfer images during online chats when creating online albums. Of course, this is mainly for the convenience of ordinary users with little computer knowledge, so that cameras, application software, websites, and so on can be combined to easily complete some silly functions.

11. Image Storage Format

Because the image files taken by digital cameras are large and the storage capacity is limited, images are usually compressed and then stored. The most common image storage formats are JPEG and Tiff compression. After JPEG compression, the file size can be changed to about 1/4, 1/8, or 1/16, saving a lot of storage space, however, this will also cause loss to original image data. Many cameras will provide specific compression ratios for users to choose from.

The TIFF file is almost uncompressed, so the image is more complete than JPEG. However, because the higher the image resolution, the smaller the compression, the more memory space occupied, the image quality requirements and memory capacity must be taken into account. For example, an 8 Mb smartmedia memory card stores 640 × 480 resolution, and 80 photos in highly compressed format, however, if you store 1024x768 images in an uncompressed format, you can only store three images. The difference is actually very large. Therefore, you must preset the storage mode or simply prepare enough memory cards before shooting.

12. lossless and lossy compression

Lossless compression and lossy compression are two types of Digital Image File compression.

Lossless compression is the compression of the file itself. Like the compression of other data files, it is the optimization of the file data storage mode, using a certain algorithm to represent duplicate data information, the file can be completely restored without affecting the file content. For digital images, the image details will not be lost. Lossy compression changes the image itself, while retaining a large amount of brightness information while saving the image, and merging the color and purity information with the surrounding pixels, the compression ratio varies depending on the merging ratio. Because the amount of information is reduced, the compression ratio can be very high and the image quality will decrease accordingly.

13. gt Lens

A gt-type lens is a multi-set combination of multiple sets of ingenious lens components that can be uniquely designed by Meida. The lens uses high-grade Low-dispersion optical glass, including multiple Die-Casting Non-spherical lenses. That is to say, the lens used by the G series high-end professional traditional camera (yinyan camera) of Meida is called the AF lens, while Meida applies the technology of producing G series lenses to the design and production of digital cameras, the product is called the GT lens.

14. Zeiss shot

Zeiss. Zeiss is a German enterprise dedicated to Application Research and contributing to the development, manufacturing and sales of high-quality products such as optics, glass technology, precision technology, and electronics. Starting from 1846, carl Zeiss has already opened a workshop for producing the microscope. Zeiss lens, professional camera, photography Lens

15. Wide angle mirror

That is, wide angle, also known as short focal lens. Due to the very short focal length, the scenes projected on the negative film become smaller and the shooting angle of the expanded lens is reduced. In addition to shooting more scenes, images with a wide angle can be captured in a narrow environment.

16. iesp automatic focus

The abbreviation of Intelligent Electronic Selection Pattern in iesp English. Iesp auto-focus is a digital camera that performs multi-Block Segmentation within the focus range (data is called slice splitting), and then performs a comprehensive calculation of the focal point location measured by the split block, determine the optimal focal length based on the status of the subject. Iesp is often seen in the introduction to Olympus digital cameras.

17. Zoom

Another focus of the lens is the zoom capability. The so-called zoom capabilities include optical zoom and digital zoom. Although both of them help to zoom in on distant objects during shooting, only optical zoom can support image subject imaging and increase more pixels to make the subject larger and clearer. Generally, the greater the zoom factor, the more suitable it is for shooting at wangyuan. The same as the traditional camera design, optical zoom depends on the focal length of the lens, so the resolution and image quality will not change. Digital zoom can only reduce the size of the original image to make the image larger on the LCD screen, but it does not help to make the details clearer. Therefore, when purchasing a digital camera, we often recommend that you pay attention to the multiples of the optical zoom. Currently, mid-range cameras generally have about three times of optical zoom, but there are also products with super-long zoom functions, such as 10 times of optical zoom.

18. optical zoom

The zoom mode is achieved by the optical lens structure. The zoom mode is similar to that of the 35mm camera, that is, the camera lens is moved to zoom in and out the scenes to be taken. The larger the optical zoom factor, the farther you can take a picture. Most of today's digital cameras have an optical zoom ratio of 2 to 5 times, and some code cameras have 10 times the optical zoom effect. The optical zoom ratio of the home video recorder is 10 ~ 22 times to clearly capture things 70 meters away. How can I make Yao Hui, a drug-infected man, look at the tomb of Ji, and see Gong Yu? BR>
19. Digital zoom

That is, digital zoom is actually the electronic enlargement of the image. It is used to enlarge a part of the original CCD image sensor using the "interpolation" processing method, the pixels on the CCD image sensor are enlarged to the entire screen by interpolation. Through digital zoom, the image is zoomed in, but its definition may decrease to a certain extent, a little like the zoom function in VCD or DVD. Therefore, digital zoom does not have much practical significance. Currently, the digital zoom of a digital camera is usually about 6 times, and the digital zoom of the camera is about 44-600 times. In actual use, 40 times is enough. If the zoom factor is not enough, we can add a multiplier in front of the camera. If the shooting angle is small, you can add a wide angle mirror accordingly.

20. Smart zoom

New unique Sony smart zoom function. it can be zoomed in and zoom out, so that no particles are zoomed in, so that the enlarged image can maintain the original quality of detail. the intelligent zoom function provides enhanced zoom functions to different degrees based on different image sizes. unlike digital zoom, smart zoom ensures the same image quality as the original image.

21. Procedural Automatic Exposure

Procedural Automatic exposure is the combination of electronic technology and artificial intelligence. When using this method, the camera can not only calculate the appropriate exposure according to the light conditions, but also automatically select the appropriate exposure combination.

22. superfocal Length

Because the rear depth of the lens is relatively large, it is said that the distance for clear imaging after focus is the superfocal length. A dummies camera generally uses the superfocal length, and uses the short focal lens to clearly imaging the scenes after a certain distance, saving focus, generally, low-end dummies cannot focus automatically, but they only use the superfocal length. As mentioned above, "clarity" is not an absolute concept. The scenes within the super focal length range are not truly clear imaging. because they are not in focus, they must be blurred ,, the reason is that the degree of blur is acceptable to the average person.

23. Interpolation

Interpolation, also known as "resetting samples", is a method to increase the pixel size of an image without generating pixels, calculate the color of the lost Pixel based on the mathematical formula of the surrounding pixel color. Some cameras use interpolation to artificially increase the image resolution.

24. Super had Image Sensor

Built-in CCD image sensors that use the "super hole accumulation diode (had)" electronic image quality improvement technology to improve the sensing performance of CCD and enhance digital signal processing functions, effectively reduce noise and unnecessary interference during image shooting, make the image clearer and clearer, and have a clearer color hierarchy. This is especially effective for scenarios with insufficient light sources or night scenes.

25. TTL Optical Measurement

That is, TTL light measuring. Measuring the light passing through the lens is irrelevant to the exposure, aperture focal length, and other parameters of the filter. The metering methods include average, local, and central light measurement. The Method for Measuring Light is similar to that for any other method. However, different lighting methods, such as backlight, have extremely different light and shade contrasts, or use methods such as micro photography.

26. ISO photosensitive Value

The ISO sensitivity value is the measured value of Light Sensitivity of traditional cameras. It is usually represented by ISO digital. The larger the number, the stronger the light sensitivity, commonly used Representation Methods include ISO 100, 400, 1000, etc. Generally, the higher the sensitivity, the thicker the film particles, and the worse the effect after amplification, digital cameras also apply this ISO value to indicate the exposure of the metering system. The lower the benchmark ISO, the higher the exposure required.

27. Storage Media

Image Storage media is a device for storing images in digital cameras. It is generally called a memory card. The memory card used by digital cameras on the market has three specifications: Smart media: small size, the price is lower than that of CF, and the maximum capacity is 64 mb. You can use a disk adapter, card reader, or PCMCIA as the transfer device. Compactflash: The price is relatively high. It is a little thicker than the sm, And the capacity is large. The maximum size is 128 MB. The speed is fast. The switching device is card reader and pcmcia. Memory stick: currently, it is a memory specification dedicated to Sony and can only be used on Sony machines.

28. Cf flash card

Compact flash card ). A digital camera is inserted like a PC Card. It can be used as an adapter (also known as a adapter) to adapt to standard PC card readers or other PC Card devices.

The CF memory card adopts reinforced glass and metal casings. the CF memory card adopts the standard ATA/ide interface and is equipped with a dedicated PCM-CIA adapter (adapter ), laptop users can use it directly in the PCMCIA slot, making it easy to transfer data between a digital camera and a computer.

29. sm flash card

Smart media is a storage media. The SMK card uses sstpd/flash memory card and features ultra-small, ultra-thin, ultra-light, and other features. The size is 37 (long) × 45 (WIDE) × 0. 76 (thick) mm, weight 1.8g, low power consumption, easy to upgrade, SM conversion card also has a PCMCIA Interface, convenient for users to transmit data.

30. Memory Stick duo

Memory Stick duo is a miniature memory stick. Its size and weight are about 1/3 of that of a general memory stick. Currently, its maximum storage capacity can reach 128 MB.

31. Uca

UCA is a digital camera storage medium produced by lexar. It has the same shape as a general cfcard and can be used on digital cameras, PDAs, MP3, and other digital devices using the cfcard, at the same time, it can be directly connected to the computer system through the USB interface for Mobile storage.

32. Digital Film

Digital Film is a storage medium for digital cameras produced by lexar. It is similar to Hitachi's smcard, Panasonic's SD card, and Sony's memorystick.

33. PC Card Converter

A connection plug-in that inserts a CF card or an smcard into the card, and then inserts a PC card into the pcmica plug-in of the computer as a whole. This is a common extension interface commonly used by hosts, you can access the pcmica memory card, pcmica hard drive, and pcmica modem.

34. IrDA infrared interface

IRDA is short for infrared data association. IrDA is an infrared wireless transmission protocol and a wireless transmission interface based on this protocol. Digital cameras that support the IrDA interface can transmit digital photos wirelessly to other devices that support IrDA communication, such as laptops or printers.

35. LCD framing

This is an essential method for most digital cameras. The only advantage of LCD scene retrieval is the only drawback of correcting common optical scenes. However, like Windows 98, it fixes Windows 95 bugs and generates more bugs. Let's take a look at the disadvantages of LCD: first, LCD is a power-consuming user, and he needs to occupy more than 1/3 of the power of the entire camera. Secondly, the LCD camera must be stretched in front of his hands to keep a certain distance from his eyes, at this time, the camera cannot obtain stable triangular support, and it is difficult to take stable and clear photos with a low-speed shutter, finally, the color and contrast of the screen displayed on the LCD are significantly different from the actual image displayed on the computer, and even if the LCD with a nominal megabixel pixel looks like the screen is still very rough, unable to observe the details of the shooting body. In the face of such images, it is difficult for you to determine whether your photos meet your requirements, fortunately, digital cameras are equipped with common optical scenes and LCD scenes almost at the same time. If you purchase a digital camera with only an LCD viewfinder, there is a certain risk, unless you are sure you can get the desired results.

36. LCD viewfinder

That is, liquid crystal display. Black and white and color are available, and true and false colors are available in color. Fake colors are cheap, but the effect is poor. Most of the LCD screens used for scenario and playback in digital cameras are currently the best TFT colors. There are two kinds of tft LCD: Reflection and transmission. The environmental light working on the front side of the reflection mode varies greatly from different angles, and the display is relatively dark, but the power is saved and the cost is low; the light working after the light-to-back is transparent. The angle changes little and the display is bright, but the power consumption is extremely high.

37. OLED

To illustrate the structure of the OLED, we can make a simple analogy: Each OLED unit is like a hamburger, and the luminous material is the vegetables in the middle. Each OLED display unit can be controlled to produce three different colors of light. Like LCD, OLED also has active and passive features. In passive mode, the Unit selected by the row and column addresses is lit up. In the active mode, there is a thin film transistor (TFT) behind the OLED unit, and the light-emitting unit is illuminated under the TFT drive. Active OLED is more power-saving, but passive OLED display performance is better.

Compared with LCD, we will find many advantages of OLED. OLED can emit light on its own, while LCD does not. Therefore, the OLED is much brighter than the LCD, the contrast is large, and the color effect is good. There is no restriction on the perspective scope of the oled, and the angle of view can generally reach 160 degrees, so that it will not be distorted from the side. The LCD needs to be illuminated by background light. The OLED only needs to be powered on by the lighting unit, and the voltage is low, which makes it more energy-saving. The weight of an OLED is much lighter than that of an LCD. There are few materials required for OLED, and the manufacturing process is simple. The cost of mass production is 20% less than that of LCD. However, the main disadvantage of OLED is that its service life is shorter than that of LCD. At present, it can only reach 5000 hours, while the LCD can reach 10000 hours.

38. TTL single-Trans framing

This is an essential way for professional cameras, and it is also an optical method that truly has no errors. The range of the viewfinder can reach 95% of that of the live image. The only drawback is that if the lens is too small, the viewfinder will be very dark, affecting manual focus. Fortunately, auto focus is now available, and this disadvantage is no longer serious. Of course, in order not to be too dark, the manufacturer will use a large-caliber advanced lens, so it is generally equipped with a semi-professional camera. Olympus is often used on cameras.

39. Electronic View

Electronic viewfinder (EVF), the use of electronic scene field rate is much greater than the optical lens, such as Sony dsc-f707 EVF field rate reached 99%. The electronic viewfinder is also more practical. This method is not only cheaper, but also saves power when used, and can be used in any ambient light. Although the visual angle and color effects in the viewfinder are not the same as those in the final result, they will soon be used.

40. Optical viewfinder

In traditional popular cameras, a set of lens components that are not relevant to the shooting lens (usually associated with the zoom lens on a high-end dummies) are commonly used to capture scenes. The cost is low, but there is a parallax, what we see is not exactly what we get.

41. Common optical framing

This is the most common way to get the scene. Its only drawback is that it has a large error. A friend who has used a digital camera knows that when the optical viewfinder of a digital camera is shooting at a close distance, the error between the upper and lower sides of the camera and the actual scene is very different (the distance is not particularly obvious ), generally, the optical viewfinder views about 85% of the actual image.

42. Multiple metering Modes

Three light measurement modes are available: Fixed-Point Light measurement, central light measurement, and multiple light measurement modes to meet different photography conditions and objectives. The multiple lighting modes divide the image into 49 regions, and measure the light of each region to achieve a balanced exposure of the image.

43. Surrounded exposure

Bracketing is an advanced feature of the camera. When you press the shutter, the camera does not take one shot, but uses a combination of different exposures to take multiple consecutive shots, so as to ensure that there is always a consistent picture of the photographer's exposure intention. You must first set the method to surround the exposure when using the enveloped exposure mode. You can just take the shot as usual. Surround exposure is generally used for static or slow moving shooting objects, because it is difficult to capture the best shooting time of an animation to take multiple consecutive shots.

44. Pre-flash exposure

The pre-flash exposure feature allows you to use the image data received during normal shooting or macro shooting, it can more accurately measure the flash intensity and exposure value, so that the image is more exposed.

45. Redeye Protection

When a portrait is taken with a flashlight, the eyes of the person who has taken the photo have a red dot due to the reflection of the fundus vessels of the person who has taken the photo. However, the current mainstream digital cameras generally have the redeye protection function, but if it is not turned on, it will still not work.

46. Anti-manual earthquake function

There are two types of mobile shock protection functions for digital cameras: Optical and digital. The optical anti-manual shock is the same as that of traditional cameras. It is used to set special lens in the imaging optical path to detect the camera vibration and automatically adjust the optical path according to the vibration characteristics and degree, stable imaging. Digital anti-manual earthquake uses the software calculation method to correct the impact of vibration by using the imaging scanning process and the mechanical shutter opening process to obtain a stable picture. In general, the well-designed optical anti-manual earthquake system should be reliable and authentic.

47. Super infrared night camera function

Sony's first infrared night camera feature allows you to take pictures in a dark environment, even objects that cannot be distinguished by the naked eye. Now, you can take pictures clearly. Used with the slow shutter switch *, the image is more pleasing to the eye, better than before.

The slow shutter of the infrared night camera function is set to 2 segments, and the slow shutter of the Super infrared night camera function is automatically adjusted.

48. Automatic Power Saving Function

If the camera is not used for any reason within 15 seconds, the automatic power-saving function will function and turn off the LCD display (sleep mode ), this can avoid unnecessary battery power consumption or prevent power consumption when the camera is connected to the power AC adapter. when the camera is not used for a longer period of time, the automatic power-saving function will turn off the power of the camera, the length can be set on the camera for 2 to 5 minutes.

49. Fixed focus Camera

It refers to a camera that uses a fixed focal length lens. Generally, the "Dummies" camera using fixed-focus lenses is smaller than the zoom "Dummies" camera at the same price, and the imaging quality is superior, consumers who choose this type of cameras often look at the small size and excellent lens quality of the camera.

50. Zoom camera

Simply put, the focal length of the camera can be adjusted and changed, so that we can achieve different visual and shooting effects by changing the focal length of the camera. The current excellent zoom "Dummies" camera not only has a completely reassuring and satisfactory high-quality zoom lens, allowing users to adjust the composition by changing the focal length to get more satisfactory shooting results, designers also pay great attention to the characteristics of their small and beautiful styles.

51. SLR camera

Slr refers to the single lens reflection, that is, SLR (single lens reflex ). In this system, the exclusive design of the mirror and Prism allows the photographer to directly observe the images through the lens from the viewfinder. The structure diagram of a single-lens reflective camera shows that after the light passes through the lens to the mirror, it is reflected to the above focal screen and formed into an image, through the mesh and Prism, we can see the outside scenes in the observation window. When shooting, when you press the shutter button, the mirror will pop up, the shutter curtain in front of the soft film will be opened at the same time, through the lens light (image) will be projected to the soft film to make the film photosensitive, then the mirror will immediately restore to its original state, and the image can be seen again in the observation window. This structure of a single-lens reflective camera determines that it is completely shot through the lens focus, it can make the image in the observation window and the film always the same, the range of the camera is basically the same as the actual shooting range, eliminating the parallax of the Side-axis camera. From the perspective of learning photography, It is very helpful for visual framing.
A major feature of a single-lens reflective camera is that it can exchange lenses of different specifications.

52. Digital Cameras

Digital cameras are the same as traditional cameras in terms of appearance or function. They primarily capture and save dynamic or static images in an instant. The most obvious difference between a digital camera and a traditional camera is the storage media. A digital camera uses a disk or memory card that records images to access images, after the shooting is completed, it can be transmitted online to the computer using standard computer methods such as RS-232, EPP, USB, or printed directly by a printer with special functions, its biggest advantage is that when the shooting effect is not satisfactory, it can be deleted and replayed in a timely manner. At the same time, you do not need to purchase negatives like traditional cameras on storage media, which can save the cost of negatives, the printing fee is also saved. In terms of processing efficiency, digital cameras also have a significant advantage over traditional cameras. In the past, hundreds of photos were taken during an activity, it is necessary to wait for the time for flushing and mailing, but now, as long as the image is transmitted to the computer through a digital camera, then the email can be sent to the participants in real time, therefore, digital cameras are one of the most convenient Image devices in this era of efficiency.

53. Red Eye

The "Red Eye" refers to the phenomenon in which the pupil of the human eye shows red spots when a digital camera takes portrait close-up in flash mode. It can be understood that in a dark environment, the pupil of the human eye is enlarged. If the optical axis of the flashlight is close to that of the camera lens, strong flashlight light is reflected into the lens through the human fundus. the fundus has abundant capillary vessels. These vessels are red, so a Red Spot is formed. Redeye protection is a feature of flash. It pre-flashes before the official flash, narrowing down the pupil of the human eye, thus reducing the redeye phenomenon.

54. Contrast

Contrast refers to the measurement of different brightness levels between the brightest white and the darkest black areas in an image. a larger range of differences indicates a larger contrast, and a smaller range indicates a smaller contrast, A good aspect ratio of 300 can easily show vivid and rich colors. When the aspect ratio is as high as: 1, each order of colors can be supported. However, the ratio suffers from the same dilemma as the brightness, and there is no effective and fair standard to measure the ratio, so the best way to identify it is to rely on the user's eyes.

55. White Balance

That is, white balance. The color of an object changes according to the color of the projected light. The color temperature of the photo taken in different light conditions varies. For example, a photo taken in a tungsten lamp (electric bulb) lighting environment may be yellow. In general, CCD cannot automatically modify the light changes like the human eyes. So through the white balance correction, it will immediately adjust the intensity of the entire image in red, green, and blue Based on the image characteristics in the current portrait to correct the error caused by the external light. Some cameras also provide manual white balance adjustment in addition to the Automatic white balance or specific color temperature white balance function.

56. Resolution

A parameter used to measure the amount of data in a bitmap image. It is usually expressed as PPI (pixels per inch ). The more data it contains, the larger the length of the graphic file, and the richer the details. However, larger files also consume more computer resources, more RAM, and larger hard disk space. On the other hand, fake images contain insufficient data (the image resolution is low), which can be quite rough, especially when the image is enlarged to a large size. Therefore, during image creation, we must determine the correct resolution based on the final purpose of the image. The trick here is to first ensure that the image contains enough data to meet the final output needs. At the same time, we also need to take up as few computer resources as possible.

Generally, the "resolution" is expressed as the number of pixels in each direction, such as 640xx. In some cases, it can also be expressed as "pixels per inch" (PPI) and the length and width of the image. For example, 72ppi and 8x 6 inch.

PPI and DPI (points per inch) are often mixed. Technically, "pixel" (p) only exists in the field of computer display, while "point" (d) only appears in the field of printing or printing. Please note the difference.

57. Sensitivity

Sensitimetry: adjusts the camera's sensitivity according to the different intensity of the light source.

When using a traditional camera, we can choose a negative film with different sensitivity (speed) based on the brightness of the shooting environment. For example, the normal cloudy environment can be iso200, and the dark is like a stage, the concert environment can be iso400 or higher, and a digital camera also has similar functions. It changes the ISO value by changing the amplification factor of the signal amplifier in the photosensitive chip, however, when the ISO value is increased, the amplifier will also increase the noise in the signal to produce coarse particles.

58. aperture

An aperture is a device used to control the amount of light that passes through the lens and enters the photosensitive surface of the body. It is usually within the lens. F is used to express the aperture size.

Aperture f = focal length of the lens/diameter of the lens diameter

From the above formula, we can see that to reach the same aperture F value, the aperture of the long focal length lens is larger than that of the short focal length lens. The complete optical circle value series are as follows:

F1, F1. 4, F2, F2. 8, F4, F5. 6, F8, F11, F16, f22, f32, f44, f64

It is worth noting that the smaller the F-aperture value, the more light it enters in the same unit of time, and the more light it enters than the next level, for example, when the aperture is adjusted from F8 to f5.6, the Light Input volume is doubled. We also say that the aperture is increased by a level. For a consumer digital camera, the F-aperture value is often between f2.8-F16 ., In addition, many digital cameras can make 1/3-level adjustments when adjusting the aperture.

59. aperture and shutter priority

In addition to the automatic mode, digital cameras above the class level usually have two options: aperture first (Aperture priority) and shutter first (shutter priority, in some cases, you can determine a aperture value or a shutter value, and then match the shutter or aperture to show the depth of field (sharpness) or effect of the screen.

60. aperture prerequisite exposure mode

After we determine the F value of the aperture, the camera light measuring system automatically selects the appropriate shutter speed (which can be a precise and non-segmented shutter speed) based on the current light condition. A digital camera with an exposure mode turntable is usually engraved with the 'A' letter on the turntable to represent the aperture prerequisite mode (see figure 4 ). The aperture prerequisite mode is suitable for photography that focuses on the depth of field effect.

Because the focal length of a digital camera is much shorter than that of a traditional camera, the aperture of the camera is small, so it is difficult to produce a narrow depth of field. Some digital cameras have a special portrait exposure mode, which uses built-in programs to blur the foreground and background.

61. Focal Length

If you have read "F =" in the camera's English specification, the subsequent digital is usually the focal length, that is, the focal length. For example

"F = 8-24mm, 38-115mm (35mm equivalent)" means the camera's focal length is 8-24mm, at the same time, the diagonal angle conversion is equivalent to the 38-35mm focal length of a traditional 115mm camera. Generally, the focal length of the standard lens of the 35mm camera is about 28-70mm. Therefore, if the focal length is higher than 70mm, the camera supports the far-looking effect. If the focal length is lower than 28mm, the camera has the wide-angle shooting capability.

The "Focus range" is an extension of focal length, which is usually divided into the general shooting distance and the approximate shooting distance. The general shooting distance of the camera is usually marked as "from a certain public score to an infinite distance ", the class-oriented products often provide close-range shooting (macro) to make up for the inability to focus in normal shooting mode. Some cameras emphasize that they have the magical capability of supporting 1-centimeter close shooting and are suitable for shooting fine objects.

62. depth of field

When shooting, adjust the camera lens so that the camera is clearly located at a certain distance from the camera. This process is called focus, and the point where the scene is located is called focus, because "clarity" is not an absolute concept, imaging of the scenes before (close to the camera) and within a certain distance can be clear, the sum of the front and back ranges is called the depth of field, which means that all scenes within the range can be clearly captured. The size of the depth of field is first related to the focal length of the lens. A lens with a long focal length, a small depth of field, and a short focal length has a large depth of field. Secondly, the depth of field is related to the aperture. The smaller the aperture (the larger the value, for example, the smaller the F16 aperture than the F11 aperture), the larger the depth of field. The larger the aperture (the smaller the value, for example, the f2.8 aperture is greater than f5.6) the smaller the depth of field. Secondly, the foreground depth is smaller than the rear depth of depth. That is to say, after precise focus, only a short distance from the front of the focus can be clearly imaged, are clear.

63. Ring light

The tornlike flashlight is directly installed on the camera lens, and the luminous tube is a kind of lamps with a ring shape. It has a low power and is equipped with efficient lamps. It has uniform light and no shadow, and is very suitable for macro photography, it is very useful in medicine and scientific research. In close-distance and micro-distance photography, because the subject is very close to the camera, the general flashlight will produce a strong shadow, and the exposure is not easy to control. At this time, the circular flashlight is often used.

64. Mirror focal plane shutter

The intermirror shutter consists of a series of thin steel blades placed between the lens units. The shutter release button triggers a spring to enable and close the blade during exposure. This type of shutter is also called the blade shutter. The focal plane shutter is located in the camera, right in front of the film. It is named because it is in the front of the focal plane, that is, the position of the film. In comparison, the focal plane shutter has the following two advantages: first, because the focal plane shutter is installed in the camera body, rather than in the lens, the interchangeable lens is often not too expensive. But for the blade shutter, the shutter is part of the lens, so the lens containing the blade shutter will be more expensive. Second, the focal plane shutter can have a faster exposure speed, in order to understand the reasons, it is necessary to know the working principle of the focal plane shutter, the operation of the focal plane shutter is somewhat like a pair of scroll curtain. First, the first curtain is pulled up, the shutter is open, and light is allowed to shine on the film. Then, when the pre-exposure ends, the second curtain follows the first curtain and blocks the light. This is why the speed of the curtain crossing the film is limited when the focal plane shutter is working.

65. Lens MTF

The lens's MTF is a test parameter that reflects the image quality of the lens and the ability of the lens to reproduce the real world. The full name of the MTF is modular transfer function. Although the lens's MTF has been adopted by several lens manufacturers, it is not an international standard. Because digital cameras are photoelectric integrated products, especially non-professional models, lenses cannot be replaced. imaging not only reflects the imaging performance of lenses, the MTF is only one of the parameters that reflect the image quality of the lens.

66. Mirror Group

The digital camera lens consists of multiple lenses. The materials are divided into glass and plastic. Some manufacturers stressed that their camera lenses are made of glass, so the light transmittance is good and the projection image is clearer. However, at present, many test reports show that glass lenses do not necessarily bring clearer images than plastic materials, and glass lenses may also increase the camera weight, therefore, when purchasing the product, we should still be more observation-oriented and do not stick to the lens material issue.

67. caliber

Lens thread, the diameter of the front end of the camera lens.

68. Shutter

It is a device that blocks the light in front of the camera. Generally, the larger the shutter time range, the better. Low seconds is suitable for shooting objects in motion. A camera emphasizes that the shutter speed can reach 1/16000 seconds at most, so you can easily grasp the target of fast moving. However, if you want to take a video at night, the shutter time will be extended, and the effect of Silk-like water flow in common photos will be captured with a slow shutter.

As for the common B-SHUTTER FUNCTION OF SINGLE-eye cameras, although you can freely decide the length of the exposure time and the shooting elasticity is higher, most consumer digital cameras are not supported yet, the default value can be 2 seconds, 8 seconds, or 16 seconds at most.

69. shutter Time Delay

The camera does not use the focus lock function and ensures that the time from pressing the shutter release button to the start of the exposure is called the shutter time delay in auto focus.

70. shutter pre-exposure mode

After we determine the shutter speed, the camera's optical measuring system will automatically select the appropriate aperture F value (which can be a fvalue without a segment) based on the current light condition. A digital camera with an exposure mode turntable is usually engraved with an 's' letter on the turntable to represent the shutter prerequisite mode. The shutter prerequisite mode is suitable for photography that requires shutter control. The high-speed shutter can be used to condense the action, and the slow shutter can be used to turn a vehicle into a beam.

71. shutter Delay

When the camera presses the shutter, the camera will automatically focus, measure the light, calculate the exposure volume, and select a suitable combination of exposures... The time required for data computing and storage is called shutter latency.

72. continuous shooting speed

Continuous shooting speed (burst speed): digital cameras need to undergo photoelectric conversion, A/D conversion, and media recording. It takes time to convert videos or record videos, in particular, the record takes a lot of time. Therefore, the speed of all digital cameras is not very fast. Currently, the fastest continuous shooting speed of a digital camera is 7 frames/second, and it takes several seconds to continue shooting after three seconds. Of course, the speed of continuous shooting is an indicator that must be paid attention to for photojournalists and those who are well-versed in Sports photography. In general photography scenarios, you do not have to consider it.

73. Continuous snapshot Mode

In the continuous shooting mode, you only need to tap the button to take continuous shooting and vividly record the continuous action.

74. brightness

Brightness is similar to contrast. brightness is used to represent the relationship between the light and shade areas of an image. The difference is that brightness is mainly used to represent the balance between the light and shade colors, that is, the intensity between the light and shade colors, the comparison determines the number of light and shade layers.

75. polarized mirror

A polarized mirror, also known as a polarized mirror, is divided into CPL and PL. A polarized mirror is an accessory of the camera. Light itself is an electromagnetic wave. After reflection and diffuse, the vibration in a certain direction will weaken and become polarized. Therefore, the reflection on the smooth object surface and the diffuse light of the sky are polarized light, the light affects the clarity of photographic imaging. The polarized mirror can choose to let a direction of vibration through the light, so the use of a polarized mirror can reduce the reflection of the object surface, can highlight the blue sky and white clouds and dark sky, in the still life photography and landscape photography, polarization mirrors are very useful.

76. Exposure Compensation

It is also an exposure control method, which is usually around ± 2-3ev. If the ambient light source is dark, the exposure value can be increased (for example, adjusted to + 1ev and + 2ev) to highlight the definition of the image.

77. Exposure

Exposure is the most primitive factor in image composition. It is determined mainly by the aperture (Aperture) and shutter (shutter.

78. Holographic auto focus

Holographic autofocus (hologram AF) is a brand new autofocus optical system. It uses advanced laser holographic photography technology and laser points to detect the edge of the subject, even in a dark environment, you can take accurate focus photos, effectively shooting up to 4.5 metres away.

79. Color Depth

The color depth (depth of color), also known as the number of digits of color, is used to represent the color resolution capability of a digital camera. Each color of the red, green, and blue channels is a n-bit digital camera. The total number of colors is 3n, and the total number of colors that can be distinguished is 23n, for example, a 24-digit digital camera can obtain a total of 2 (24 power), that is, 16, 777, 216 colors. The more digits a digital camera has, the more details it can capture. Generally, a digital camera has enough 24-digit color digits. for digital cameras used in special industries such as advertising photography, they generally only need 30 or 36-digit color depths.

80. Flashlight

Flash is also one of the ways to enhance the exposure, especially in the dark, the flash helps make the scene brighter. However, when shooting a person, the light in the flashlight may be residual in the pupil of the eyes, and then the "Red Eye" may occur, therefore, many camera vendors have added the "Remove the red eye" feature to the design. Before the flash is enabled, the camera emits a weak light to adapt the pupil, and then executes the real Flash to avoid the occurrence of the red eye.

81. Slow synchronization of flashlight

Slow synchronization (slow) is an advanced feature that works with the camera and flash. The slow synchronization of the flashlight refers to reducing the shutter speed properly in the early morning, evening, or evening when there is a certain amount of lighting. When the flashlight is used, the background can be properly exposed while the subject is normal, rich screen effects.

There are two modes for slow synchronization: Pre-Sync and post-sync. Pre-sync refers to flashing immediately after the shutter is fully enabled. It is suitable for general situations and is convenient to capture the shooting time, for example, the character's demeanor. Post-sync refers to flashing when the shutter is about to be closed. It is suitable for shooting the animation, it can pull the Motion Track of the dispatch body to form a strong dynamic effect.

82. Flash index Gn

Flash index gn is one of the indicators that reflect the flashlight power size. A good flashlight should have a stable output and adjustable color temperature standard (generally about K, the same as that of daylight) fast Power-back, steering, and changing the illumination range. For films or digital camera settings with ISO 100 sensitivity, GN = aperture factor X shooting distance (meters ).

83. Purple edge of digital photos

The purple edge of a digital camera refers to the large contrast between the subject and the digital camera, the color spot that appears at the junction of the highlight and low light is the purple color of the digital camera ). The reason for the appearance of the purple edge is related to the dispersion of the camera lens, the small area of CCD imaging (high density of imaging units), and the signal processing algorithm inside the camera.

84. noisy or noise

Noise (Noise), which is usually produced by electronic interference. It looks like the image is corrupted and it is covered with small rough points.

85. Digital back

The digital back, also known as the digital back, is a CCD chip, digital processing, and other parts, without a lens and other mechanisms, only attached to the body of other traditional cameras can be used for shooting devices, it is a device that is attached to a Middle camera and a large camera so that the middle camera and large camera can be digitalized.

86. Dual Mode

A digital camera has two modes: static photography with a digital camera and continuous dynamic photography with a video camera.

87. pseudo colors

"Pseudo color" refers to the color stripes and noise in the dark part of the photo. This is caused by weak signals in the dark part, reduced signal-to-noise ratio, and exposure of photoelectric interference signals, because the actual image does not have interference signals, it is called "pseudo color ".

88. equivalent to 35mm cameras

Currently, the area of imaging devices of digital cameras is smaller than that of ordinary 135 films. Therefore, the focal length of their lenses is very short. When it comes to the focal length of their lenses, the actual physical focal length is not often said, the focal length of a 35mm (135 in China) camera with the same angle of view, that is to say, "The angle of view is equivalent to xx ".

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