三分钟讲清曝光原理

本***会快速给大家讲清楚曝光的原理

This video will try to explain how exposure works as quickly as possible.

首先 阳光照射到我们世界的物体上产生反射光

First镜头光圈英文名称为aperture, you have the sun which creates light that reflects upon objects in our world.

接着 你要用照相机捕捉这些光线

Then,you have a camera that tries to capture this light.

光线透过镜头进入到相机中

The light enters the camera through a lens.

在相机上有三个基本功能用于控制光线

And there are three basic functions of the camera that help control light镜头光圈英文名称为aperture,

你可以通过它们来得到合适的曝光 ***不会太亮或太暗

so that you get proper exposure, a photo that isn’t too bright or too dark.

首先 是光圈

First, there’s aperture.

光圈 也被称为虹彩光圈或F制光圈

The aperture, also referred to as the iris or F-stop,

指的是镜头里面孔洞的直径

is the diameter of a hole inside your lens.

这个孔越大 进来的光线越多

The bigger the hole取名, the more light that enters.

孔越小 进来的光越少

The smaller the hole,the less light.

大的光圈能得到比小光圈更亮的图像

Big hole equals brighter image than a small hole.

令人困惑的是较小的F制光圈值

The confusing thing is that smaller F-stop number

代表着较大的开度

represents a larger opening.

例如从f/1.4到f/2

For example镜头光圈英文名称为aperture, going from f/1.4 to f/2

光圈的尺寸是减小的

decreases the size of the aperture,

由此使得更少的光进入相机

and therefore allows less light into the camera,

如果外界特别亮 也许你必须减小

so if it’s very bright outside, you may have to decrease

光圈的尺寸

the size of the aperture,

但实际上增加了F制光圈值

but that is actually increasing the F-stop number.

接下来控制光线的功能是快门速度

The next function to control light is the shutter speed.

相机有一个快门通过开闭来

Cameras have a shutter that opens and closes to allow light

使得光线进入相机机身内部

into the camera’s body.

开闭快门的速度越快 进入的光线越少

The faster this opens and closes, the less light comes in.

即便一秒钟在我们看来可能已经很快了

Even though one second may seem fast to you and me,

但对于相机快门来说它很慢

that is very slow for a camera shutter speed,

这就意味着大量的光线进入了你的相机

and that will mean a lot of light entering your camera.

快门的速度可以比千分之一秒还快

Shutters can go faster than one thousandth of a second

这样快的快门使得我们能够拍到像蜂鸟这样运动的目标

and these fast shutters allow us to capture moving objects like this hummingbird.

所以说要记住较慢的快门使得更多的光线进入

So remember a longer shutter allows more light in,

当外界环境很暗时你就得减慢快门的速度

so you might have to slow down your shutter speed if it is dark outside.

相机上最后一个控制曝光的功能是ISO

The last function of your camera that controls exposure is the ISO.

ISO指的是相机传感器的敏感程度

The ISO is basically the sensitivity of your camera’s sensor,

是捕捉光线并将其转化为数码***的

a digital wonder that captures the light

神奇电子元件 相机ISO越高

and turns it into a digital photo, the higher the ISO,

意味着它更敏感 能得到更亮的***

means it’s more sensitive and makes a brighter photo.

增大ISO不利的一面是

The negative side to raising your ISO

当外界太暗时***会伴有噪点产生

when it’s dark is that it comes with grain.

也就是说你的ISO越高 你的***的噪点将越多

So the higher your ISO, the more grainy your photo will be.

根据相机的质量

Depending on your camera,

相机越好 ISO增大可能不会出现噪点

you’ll be able to raise the ISO higher without getting grain.

那么 摄影的艺术就在于平衡这三个功能

The art of photography is to balance these three functions aperture,

光圈孔径、快门速度和ISO来得到合适的曝光

shutter speed and ISO to get proper exposure.

在摄影老师课里 我们将会对这三个功能进行更深入的研究

In the photography masterclass dives deeper into each of these functions,

相信现在你已经对相机有了一定的了解吧

but hopefully now you already understand a little bit more about your camera

应该知道该如何使用手动模式来获得合适的曝光了

and how to use the manual functions to get proper exposure.