What details and skills do you need to pay attention to when shooting scenery with slow doors?

Usually, people call a shutter less than 1/3 second a slow door. When the shutter speed is slow enough, the camera can smooth the fluctuation of sea water and even capture the shifting stars that we seldom care about. So what details and skills do you need to pay attention to when shooting a slow door? What details and skills do you need to pay attention to when shooting scenery with slow doors?

Composition and preparatory work

There is no need to elaborate on composition. Photographers have their own opinions on which angle to shoot when arriving at a scene. Whether the tripod is placed safely, and the preparations such as the installation of cable release and gradient filter are the guarantee for the smooth shooting of the slow door. At sunrise and sunset, the light changes very obviously, while in slow-door shooting, the exposure usually lasts for about two minutes when using the 1th and 6th grade reducers (ND1 ND64), and a slight mistake in the middle may lead to the failure of the whole shooting.

Installation and arrangement order of filters in shooting:

When using a square filter system, attention should be paid to the installation order of gradient mirrors and subtractors. The light reduction mirror is in front, and the gap on the side will cause light leakage. When installing a gradient mirror to balance the light ratio, it is necessary to reserve the position of the reducing mirror.

focusing and focus locking

High-end position reducers, such as ND64 and ND1, will affect the autofocus of the camera due to the low light transmittance of the lens, so focus first, and then install the ND filter. To complete focusing in AF mode, it is necessary to switch the focusing mode to MF manual focusing mode. As long as the focusing ring on the lens is not rotated, the focus will not change.

calculate the shooting time of the slow door

before shooting the slow door, you need to take a photo with correct exposure and rich details in the light and dark parts. Use the parameters of this photo to calculate the correct exposure time after using the subtracter. ?

Light leakage, duration and thermal noise

Light leakage is the only shortcoming of the square filter system. Although the lens will be attached with light-shielding cotton, don't forget to turn off the viewfinder when shooting.

slow door shooting, door b is often used. The longer the exposure time, the more noise the camera will produce, so how long is the appropriate time to control the slow door shooting?

In slow-door shooting, there is not much difference between exposure for 2 minutes and exposure for 1 minutes, so I usually control the exposure time to about 2 minutes. When the light is weak, use a low-grade reducing mirror or increase the sensitivity appropriately to control the shooting time of the slow door. About ISO1 is not a problem for the current post-noise reduction technology.

This is a photo I took in the slow door for a long time. After more than 7 minutes of exposure, the camera will not only produce a lot of gray noise, but also the color noise will increase geometrically. In this case, it is better to use a slightly higher sensitivity to shoot, and the noise control is better.

stack or filter?

In the same plane, taking multiple photos, and later using the average stack can also simulate the effect of slow door. Is it stack or filter? We don't want to bet on shorter lengths. I think only by mastering various methods can we cope with the complex shooting environment.

Stack shooting example 1:

Benxi Green Stone Valley, the Dindar beam in the forest is very beautiful. After shooting with a subtracter, the water surface achieved the desired atomization effect, but the beam was lost a lot.

then I choose 1 continuous shooting, and use the effect of the late average stack synthesis. The stacking method not only keeps the atomization effect of the water surface, but also does not lose the charming beams in the mountains.

Stack shooting example 2:

After the rain clears, the clouds in the sky are very beautiful. When the cloud moves at a fast speed, the light and shadow between the buildings on the ground will be lost when the slow door is photographed with a reducing mirror, which leads to the lack of three-dimensional sense of the picture.

Hold the plane, select continuous shooting mode, and 3 images after average stack processing. While retaining the light and shadow on the ground, the clouds in the sky also form a dynamic effect. When stacking continuous shooting, there should be no interval between each photo, otherwise the effect of slow door will become the effect of oil painting strokes. (Just change the camera shutter release mode to continuous shooting.)