Function and Use of Hot Boot Flash

Lead: Adding 1 and two flash lights to the camera bag can make your shooting infinitely wonderful. This paper is a complete instruction manual for flashlights with different functions.

equipment

There are many flash vendors now. Some are flashlights that can be installed on hot boots, and some are large studio lights. It only says hot boots flash here. This is a very portable flash with multiple control and exposure functions.

What you need is a digital SLR camera and an original hot shoe flash? For example, Canon Speedlite EX series, Nikon Speedlight SB series, and must have the main light function (control other auxiliary lights).

Canon flash can be used as the main light:

580EX II

Nikon flash can be the main light:

SB-900

SB-800

SB-700

Although Canon and Nikon have wide product lines, only the top flash can be used as the main light. Low-end models, such as Canon 430EX II and Nikon SB-600, can only be used as auxiliary lights and receive remote control.

Some digital SLR cameras can use overhead flash to remotely control other auxiliary lights, such as Nikon D700 and Canon EOS 7D. If you already have a flash, you can now try to remotely control the off-board flash. Read the camera manual to see if your camera has this function.

How to control exposure

There are three factors for camera to control exposure:

Shutter speed

hole

ISO sensitivity

The flash gives the photographer a fourth tool to control the light. Otherwise, the photographer will be affected by the ambient light. Of course, you can use reflectors and other tools, but these are not what we are going to discuss here.

Let's take a look at the common functions of these flashlights.

TTL flash control

TTL is? Through the lens? Abbreviation of, meaning? Through the lens? . Almost all single-lens cameras have this built-in metering function. Nikon has E-TTL, Nikon has i-TTL. This function puts the hand-held exposure meter into the camera and measures the brightness and color of the scene through the incident light of the lens. Because the final imaging light is measured, no additional conversion is needed.

TTL camera can automatically judge the scene exposure value, and when the selected exposure value may be overexposed or underexposed, it will remind the photographer (M file) or make automatic adjustment (automatic file).

The flash with TTL function will receive the TTL photometric results from the fuselage and automatically determine the flash output. However, even in automatic mode, you can manually adjust the output according to the automatic value through flash exposure compensation.

Flash exposure compensation

The method of adjusting TTL flash output is similar to the method of adjusting camera exposure compensation. Both the overhead flash and the external flash can be adjusted.

Through flash exposure compensation, users can select the output in the range of 5 levels (-2Ev-+2Ev). 0Ev is the result of automatic calculation by the camera according to TTL.

The flash can not only overwhelm the ambient light, but also keep the balance of 50/50. Therefore, you can use different flash outputs to meet different environmental requirements.

In the above picture, I use flash as the main light source and ambient light as the filling light source. This is done to eliminate the annoying green color of fluorescent tubes. So I improved the exposure compensation of the flash, flooded the ambient light and eliminated the color projection.

Flash surround exposure

Flash bracketing exposure (FEB) works in the same way as camera automatic bracketing exposure (AEB). In this mode, users can select a specific step size (1/3, 1/2 or 1Ev), and they will shoot at various exposure value. Generally, a * * * will take three pictures (0Ev, +Ev, -Ev).

When it is difficult to judge whether the exposure is accurate through the LCD screen, the enclosed exposure can make the shooting result more reliable.

Flash exposure lock

Flash exposure lock (FEL) is a useful function, which can force the flash to keep a fixed output. The output of TTL automatic flash is not fixed, so it is very helpful to use FEL in Gao Fancha, backlight or other situations that may make the camera metering system invalid.

For example, if a person wears white clothes, the camera's metering system may mistakenly think that the scene is bright. Then in the same scene, another person is dressed in black. Results The camera's photometry will get different results, and the use of free electron laser can ensure the stable output of the flash.

Manual flash

Like a camera, the manual mode is the most monotonous, but it can provide the best control and accuracy. The top flash provides step-by-step adjustment from 100% output to1/28, 1/3, and from 14mm to 105mm (Canon) or 200mm (Nikon SB- The advantage of manual flashing is stable output. After setting, the flash will keep the same output.

Manual flash allows photographers to have consistent light throughout the shooting process, no matter how the ambient light changes. In this way, the photographer can control the ambient light through the shutter speed, and use the environment and the flash as two independent light sources.

This photo was taken with a manual flash. The room is very dark, and the light in the doctor's hand will give off strong light, which will make the camera metering system ineffective. It takes a lot of attempts to take accurate exposure photos with TTL automatic flash mode.

In addition, manual flashing can exceed the 5-level adjustment range of TT system. Sometimes the compensation of +2 or +3Ev is not enough to compete with the sun outdoors, especially small flashlights.

In the following photo, I used two 580EX II? News? Live in the afternoon sunshine. The sun is very bright, so it is not enough to compensate two flashlights with +3Ev and zoom to 105mm in TTL mode. I took this photo in manual mode and set it to 100% output.

Flash zoom

The zoom of the flash will change the size of the light beam, which is consistent with the field of view of the lens at a specific focal length. In TTL mode, the focal length of the flash will automatically match the focal length of the nearest lens.

Changing the focal length of the flash will also change the projection distance and intensity of the light beam.

The reason for using the flash zoom function is to control the projection range of the light beam. By reducing the focal length, the light can cover a wider range and the light becomes less intense; Increase the focal length, the light beam will gather and the brightness will be stronger.

High speed synchronous/focal plane flash

High-speed synchronization/focal plane flash when maximum synchronization speed is required? Is it usually 1/250s? This is a very useful model. In this mode, you can even use 1/8000. This mode is especially suitable for the aperture priority mode of the camera.

In this mode, the flash will emit a series of high-frequency flashes instead of ordinary flashes. This pulsed light ensures that the whole photo can be exposed. However, the cost of this working mode is the sacrifice of strength, so usually the flash needs to be close to the subject.

When the flash is close enough, it can capture moving objects and fill shadows at the same time in the midday sun. Remember, the faster the shutter speed, the closer the flash needs to the main body.

Hou Lian synchronization

By default, the flash is synchronized with the front curtain? Blinking when the first shutter is opened. In Hou Lian synchronization mode, when the second curtain starts to close, the flash will flash. This mode is very helpful when shooting the motion trajectory with a slow shutter.

Using Hou Lian to photograph moving objects synchronously, we can photograph the moving track. If you synchronize with the front curtain, there will be moving objects behind and tracks in front. A mistake? Images.

Frequency spark

Not many photographers will use this function, but it is also a very useful function, which can shoot cool effects. Strobe refers to the continuous flashing and output at a certain frequency during exposure. The frequency depends on the flash output, and the higher the output intensity, the lower the frequency.

Ideally, the exposure time is only 2s, and the best shooting effect is in a completely dark space. Of course you need a tripod. Once the exposure is started, the flash will flash according to the frequency.

For example, strobe can shoot a small ball that beats continuously.

Radio trigger

Off-plane flash is the most interesting part of flash photography, and many hot shoe flashes can realize wireless flash. There is no need to connect cables between the flash and the camera, and the lamp can be placed almost anywhere. Wireless flash not only liberates the photographer's creativity, but also simplifies the confusion caused by equipment and too many cables.

There are many ways to use wireless flash, but most modern flash and cameras support an advanced flash function of main and auxiliary lights? Use one main light to control other flashlights. What kind of main light is called? Master? (Canon) Or? Commander? (Nikon) At present, only the top flash can be used as the main light, and other low-end models can only be used as auxiliary lights.

The auxiliary lights can be triggered in the following ways: light, infrared and short wave. Some advanced large-scale studio lights not only support all three modes, but also support the fourth mode: networked control.

In order to control the auxiliary light, it is necessary to set the flash to? Main light? And then what? Auxiliary light? Mode, the auxiliary lamp must be compatible with the signal from the main lamp. Take Vida 285HV flash as an example, it supports light flashing or wireless flashing through wireless devices such as PocketWizard.

Canon and Nikon have their own wireless flash systems. Usually, four lights are a group, and at most three groups (TTL mode) are supported. In manual mode, more lights are supported.

Photographer joe McNally mixed the flash? Even a crazy number? And famous. He can shoot a plane or a large group of people with 50 hot-shoe flashes.

light ratio

This is a topic about wireless flash and flash exposure compensation. When shooting with multiple lamps, there is a light ratio between several lamps or groups of lamps.

In the case of two (group) lamps, the light ratio can be: 8/ 1, 4/ 1, 2/ 1/2, 1/4, 1/8.

11light ratio means that two (group) lamps output the same light. Under the light ratio of 4/ 1( 1/4), the output of one lamp is 1/4 of another lamp. These light ratios depend on the flash exposure compensation value set by the photographer.

abstract

I hope this article can help you understand the function and usage of flash lamp for fever-reducing boots. Remember that not all flashlights have all the above functions, but most of them do.