What does the camera light ratio mean?

Question 1: What does the camera light ratio mean? A camera has no light ratio, which refers to the amount of light received by the subject.

For example, if there are two lamps, one on the left and the other on the right, which illuminate the object at the same distance, one with power of 100W and the other with power of 200W, then the light ratio of the object is 1:2.

Question 2: What do aperture and sensitivity in a camera mean? The simpler the better, the simpler the better.

Aperture: used to control the amount of light entering the image sensor, and also has the function of controlling the depth of field. The larger the aperture, the more light enters the image sensor and the smaller the depth of field. The smaller the aperture, the less light enters the image sensor and the greater the depth of field.

Sensitivity: The sensitivity of an image sensor to light. The higher the ISO sensitivity, the more sensitive the sensor is to light, but too high ISO will increase the number of particles in the photo.

Question 3: What exactly do the exposure and aperture of SLR mean? What does exposure mean? In photography, there are only normal exposure, underexposure and overexposure, and I have never heard of any exposure rate.

Just compare the light with the water in the tap. The aperture is like a switch, and the shutter speed is the speed at which you open the water pipe. When we receive water, if we want to receive more water, we should turn on the tap switch and keep the water pipe open for a long time. When there is little water, turn down the switch and turn on the water pipe for a short time.

Photography is the projection of light on a negative (CCD, CMOS). The amount of light passing through the camera is controlled by the aperture. Turn on the big aperture when the light is insufficient and turn on the small aperture when the light is too strong. Of course, it can also be adjusted by the shutter speed. The specific methods should be adjusted according to your creative requirements.

Question 4: How to reduce the light ratio of Canon camera How to reduce the light ratio of the shot picture is related to the strength of the light source and the width of the photographic material (or component) of the camera image, and has little to do with the brand of the camera, so is Canon camera. Generally speaking, the larger the area of the image sensitive element of the camera, the larger the tolerance range when the exposure light ratio is too large. A large-format camera with the same price as a Canon camera is obviously superior to a small-format Canon camera when shooting scenes with large light ratio.

There are generally two situations to reduce the light ratio:

The large light ratio formed by artificial light source can control the intensity of light source, change the direction and intensity of light projected on the photographed object, or control the intensity, direction or intensity of background lighting.

For natural light sources, only human light sources can be added to change the illumination of the subject or background.

Question 5: What's the difference between a digital camera and an optical camera? Digital cameras also need optics. . . .

This question is actually not valid.

Are you talking about digital zoom and optical zoom?

Optical zoom means that each focal length is shot at the real focal length, while digital zoom means that after a film shot at the wide-angle end is cut, all focal lengths except the wide-angle end are hard-drawn, and the accuracy is of course far less than that of optical zoom.

Question 6: What's the difference between a large aperture and a small aperture of a camera? The larger the aperture, the more the feed, and the smaller the aperture, the less the incoming light. (f/3.5 is a large aperture and f22 is a small aperture) The smaller the aperture, the larger the aperture and the smaller the aperture! I hope to help your brother! This is another key word for your camera:

ISO and image quality

ISO is a word with high exposure. When we buy cookies in the supermarket, we may see that our company has passed the ISO900 1 quality system certification on the packaging. This ISO is the abbreviation of International Organization for Standards. The International Organization for Standardization (ISO) has formulated the standards for biscuit management and film production, so there are several films on the shelves, namely ISO100,200 and 400, which are films with different photosensitive speeds. ISO sensitivity is the sensitivity of CCD (or film) to light. If ISO 100 film is used, if the camera can correctly expose within 2 seconds, then under the same light conditions, it only takes 1 second to use ISO200 film and 0.5 second to use ISO400 film. In the digital age, there are ISO options in the main menu of digital cameras, such as 100, 200, 400 or 800, just like those on film. Depending on the model, from ISO50 to 25600, the higher the number, the more sensitive it is.

Fast food is popular for lunch and love, so we should do everything quickly. It is reasonable that we like high sensitivity. However, there is no free lunch. Although high ISO is fast, the image is rough and cannot stand fine magnification. Therefore, landscape photography needs the lowest sensitivity of the camera to get a fine picture. High ISO is usually used only as a last resort.

People can't help themselves in rivers and lakes, and sometimes they have to, so high ISO image quality is one of the most important indicators of digital cameras. In dark places, such as dark rooms and midnight streets, even if the aperture is opened to the maximum at ISO 100, the shutter speed needs 1/4 seconds or even slower to properly expose. At this time, it is impossible to stabilize the camera without a tripod, and the photo will be burnt when the hand is shaken; Even with a tripod, as long as the subject turns his head, the photo will be posted. Flash can save the emergency, but it will destroy the atmosphere at the scene and make people look unnatural. Moreover, the effective distance of the small flash in the camera will not exceed four meters, and people and scenery that are a little farther away can't be photographed. What's more, flashlights are not allowed in some places, such as museums and theaters. We have no choice but to improve the sensitivity of digital cameras to ISO800 or even 1600.

Small digital DC and digital SLR DSLR, which are also/kloc-0.0 million pixels, will not have much difference in resolution and image quality if they shoot at the lowest sensitivity (such as ISO 100 or 80), assuming the lens quality is the same. However, if the ISO is raised to 400 for shooting, the difference in image quality will be obvious. The image taken by DSLR is still relatively clean, which is not much different from that taken by ISO 100, while the image quality of DC is obviously degraded, with great noise, distorted color and lost details. If we continue to upgrade to ISO800, the image quality of small digital DC can only be described in four words, while the image quality of digital SLR is acceptable although it has declined. If it is further upgraded to ISO 1600, the image quality of most digital SLR will be greatly reduced, but it can still meet the needs of enlarging 10 inch photos. At this time, the picture quality of the small digital DC is poor, and it takes a brave heart to dare to watch it.

In the case of equal pixels, the larger the CCD area, the better the imaging quality of high ISO. That is to say, when the CCD area is fixed, adding more pixels inside will lead to the decline of image quality. Therefore, the current digital camera should not simply add a few million pixels to the 6.5438+million pixels, but should work hard to improve the quality of CCD. It is urgent to reduce the noise level of high sensitivity (high ISO) and increase the exposure latitude.

Travel photography 8 million pixels is enough. When choosing a digital camera, we should not only look at the pixel height, but also pay attention to the size of the camera CCD. It's 2008, and the resolution is enough. It's time to pay attention to the picture quality.

shutter

In those years when photography was just invented, it usually took several minutes to take a picture. Most cameras don't need a shutter. At the beginning of exposure, take off the lens cover, then look at the watch. After five minutes, cover it and the photo will be finished.

Later, the photographic speed of film became faster and faster (ISO became higher and higher ... >>

Question 7: What do optical zoom and digital zoom in SLR cameras mean? I think most SLR configurations are 0 times. The lens and fuselage of a SLR camera are separated, and the zoom factor is the lens parameter rather than the fuselage parameter, so the label 0 indicates the ratio of the shortest focal length to the longest focal length.

Question 8: Generally speaking, isn't the bigger the aperture of a camera, the better? Why is the aperture f3.5 of SLR camera smaller than that of mobile phone f2.2? Is that what you think? The data of the aperture is like this. The smaller the number, the larger the aperture. However, the aperture is only a numerical value, which cannot directly represent the amount of light entering a lens and the actual diameter of the aperture. For example, the 3.5 of your SLR is smaller than the 2.2 of your mobile phone, and the aperture is conceptually like this. However, that number is only a digital standard indicator, and even you will find that some lenses of SLR have a large aperture, but the maximum aperture is not smaller than that of small aperture lenses. As for whether the greater the amount of light, the better. It can only be said that the amount of light entering is determined by the aperture size, lens aperture and lens structure. The larger the aperture, the simpler the lens structure and the greater the light input. However, it cannot be said that the greater the light input, the better the lens, because there are many aspects to measure a lens, such as the workmanship of the lens, the quality of the lens, the size of the aperture, the internal structure of the lens and so on.

Theoretically, the light input of large aperture is larger than that of small aperture, but that is under the same other conditions. For example, the 3.5 aperture of a SLR lens is not necessarily smaller than that of a mobile phone.

Question 9: Excuse me, Master, how to arrange the light, what is the light ratio, the camera parameter setting, are there any special requirements for the camera and lens? There is no guarantee to pay the teacher 3000 yuan, because it depends on the students' understanding. You can take pictures with a certain light ratio. Now is the digital age, and the requirements for such pictures are not high.