What's the use of external flash?

Question 1: What is the use of the external flash of the SLR? 1. When the light is insufficient, use a flash to fill the light.

2, color cast, you can use a flash to correct the color.

3. When the contrast is large, you can use a flash to reduce the contrast.

Whether it is a traditional machine or a digital machine, the camera and the human eye see the same thing. The camera will be clearer when the light is good. When the light is bad, the human brain can blur the image it sees, but when the machine is blurred, people will see it again, so the light is very important for photography, and the flash is an important prerequisite for the camera to shoot high definition. Sometimes even if the light and natural light are good, the angle of the light source is not necessarily ideal, so the flash is a camera that removes sunlight and flowers.

Question 2: I want to know the function of the external flash. Generally speaking, when you want to make various changes in flash photography, or use a flash with a large output (that is, the brightness of the flash), there are many restrictions on using the built-in flash of the camera alone. Therefore, for beginners who want to use flash photography advanced, we will recommend buying a powerful external flash to match. There are two types of external flash lamps: one is a general model, which can be used for cameras of different manufacturers, and the other is a special model, which can be used for specific cameras. The built-in flash of a digital camera will directly shine strong light on the subject, so sometimes it will produce ugly shadows. At this time, it is best to use an external flash. Recently, more and more digital cameras can use external flash. If it is a model that can use an external flash, it would be a pity not to use it. Here, let's first understand the relevant terminology explanations of flash application. Look at the GN value first. In the specification table of the flash lamp, the Guide number represents the power of the flash lamp, and the GN value refers to the output degree of the flash lamp. The greater the GN value, the stronger the flash output, that is, the stronger the flash ability. The calculation method of GN value is: GN = f (aperture) x m (in meters, representing the distance from the subject). In this formula, the shooting environment is based on ISO 100. For example, the GN value of the flash is 40. When we shoot with the aperture of F4, the effective distance of the flash can reach the range of 10 meter. Next, let's take a look at several different operating modes of the flash when shooting. At present, the working modes of external flash in the general market are: M mode, A mode, TTL mode, and higher-order flash will also have FP mode. Let's briefly explain these patterns. M mode: full manual mode, the user must adjust the output of the flash according to the aperture and distance used in shooting. The advantage of M mode is that the output is consistent. As long as this value is adjusted, the output of each shooting flash will be a fixed amount of light. The disadvantage is that it needs to be adjusted in advance, and it takes a lot of time to calculate the adjustment strain on site. A mode: automatic mode, first measure the environment with the light sensor on the flash, and then apply force with the aperture setting of the camera. The operation principle of mode A is similar to that of mode M, except that the work of adjusting the output and metering is done with a flash, and the photographer only needs to adjust the required working aperture. TTL mode: TTL mode will measure light according to the exposure combination set by the camera, and start to emit light as soon as the shutter is pressed, and then calculate the light quantity according to the TTL exposure of the camera until the exposure is sufficient. Generally speaking, as long as the camera's metering system is accurate enough, TTL mode can be used to obtain more suitable exposure. The disadvantage of TTL is that the contrast is too large, or when shooting in an all-black or all-white environment, if there is no proper exposure compensation, the photos will be too bright or too dark. FP mode: FP high-speed synchronization. In this mode, the shutter speed of the flash is no longer limited by the shutter speed of camera flash synchronization, and the flash with FP function can be synchronized with the highest shutter of the camera through strobe mode. However, when using FP mode, the output will be reduced due to continuous stroboscopic. In addition, the term "illumination angle" should be mentioned. The illumination angle refers to the illumination angle range that the flash can cover when using the lens. Generally speaking, the lighting angle of the flash lamp on the market at present is generally 24 mm to 85 mm, covering the wide-angle end to the medium-long focal length commonly used in our photography. Advanced flashlights will install a "diffuser" on the lamp head. After being pulled down, the illumination angle of the flash can be widened to 16mm, and this focal section has covered the ultra-wide angle range. Remember, when using an APS-sized DSLR, first multiply the focal length of the lens by 1.5 or 1.6, and then correspond to the illumination angle of the flash. When looking at the specification table of flashing lights, the above nouns should be familiar with the content first, and then talk about the basic operation and application of flashing lights. The following are some problems that should be paid attention to when using external flash: 1. After testing some commercial digital cameras in the market, it is found that most digital cameras only support the flash of this brand, and the flash of other brands may be out of sync. Users are advised to choose the flash of the same brand as the digital camera. 2. Although some digital cameras can be equipped with flashlights of other brands, there are still certain requirements when using them ... >>

Question 3: What is the use of the external flash of the SLR camera? First of all, the built-in lights and cameras grab electricity, which is not enough;

Secondly, the outside light is bigger and it shines far. Finally, the external light angle is different and adjustable, and the internal light is too close to the lens.

Question 4: What is the use of the soft cover of the external flash? When using flash, soft mask can eliminate the high points of the subject, but it can't completely eliminate the projection. Moreover, people are close to the back of the scene when taking pictures, and even if the light is scattered again, there will be shadows.

If the ceiling of the shooting position is white, you can adjust the angle of the flash so that the flash can shoot upwards, and it may be better to take a photo of the certificate by using the light reflected from the ceiling.

Question 5: What is the function of the external flash of SLR? What are the advantages compared with the self-contained flash? The function difference between the overhead flash and the external flash of the SLR camera is as follows:

1, the set-top box flash of the SLR camera is folded and placed on the protruding parts of the five prisms of the set-top box. Due to the limited storage position, the height of the lamp holder is limited when it is opened for use. When a SLR camera uses a telephoto lens, the long lens and its hood will block the light emitted by the dome light, resulting in an arc shadow at the lower part of the picture (as shown in figure 1). The external flash installed at the position of hot shoes has enough height, and the long lens and its hood will not block the light (as shown in Figure 2).

Figure 1

Figure 2

2. The self-contained flash of the SLR camera is powered by the battery of the fuselage. Considering the power consumption, the general flash index is only about 8- 12. The external flash is equipped with 2-4 AA batteries. The flash index is as high as 24-60, and the lighting distance is large.

3. The lamp holder of the SLR camera with its own flash cannot rotate freely. The lighting direction always faces straight ahead. Single-lamp frontal lighting in portrait photography is easy to make the face lose its three-dimensional sense, and annoying shadows will appear in the background. The lamp head of the external flash can be rotated up and down by more than 90 degrees, and left and right by 180 degrees, so that it can "flash" 45 degrees conveniently (using the reflected light from the roof or wall), creating a lighting atmosphere similar to natural light, adding a three-dimensional sense to the face of portrait photography, and effectively preventing background shadows.

Figure 3, Jumping Flash

Because of the advantages of external lights, many high-end professional SLR cameras even give up simple overhead lights.

Question 6: Does the external flash of SLR camera have a great effect? Is it necessary to buy it? If it is portrait photography, one or two more lights are like one more good lens. Still have to calculate.

Question 7: Ask to recommend an external flash for 20 minutes, depending on your needs and the degree of fever. Do you want to buy a high-speed synchronous flash, domestic brand Jebel? God cow? Yongnuo has high-speed synchronous flash, which is not bad. I also want to continue to play better and burn more. I can also add two high-speed synchronizers to flash off, which is easier to use and can imitate different light levels.

Question 8: What is the difference between the external flash and the internal flash of a camera? Simply put, the built-in power is limited, and the effective flashing distance is generally about 5 m. Because of the fixed position of the lamp, many effects cannot be realized.

The external power is generally relatively large, the effective distance of flashing can reach about 20 meters (of course, there are differences in different distances), the lamp position is flexible, and the effect is in your own hands.

Question 9: How to use the external flash of the camera 1? Buy a matching external flash.

2. Set the flash according to the flash description and your actual needs.

Question 10: Is the SLR external flash useful for photographers? It is very useful. Bring your own flash to shoot the light directly, and the color of people is very hard. The external flash has a reflector, which can make the light much softer. When a flash is needed, the effect of an external flash will be much more natural.