p光圈和dc光圈的区别

Read any good photography tutorial—including all the ones on this site—and you’ll see one bit of advice repeated over and over again: shoot using Aperture Priority mode. So, why do so many professional photographers love Aperture Priority? What makes it so good? Let’s find out.

阅读任何优秀的摄影教程(包括本网站上的所有摄影教程)，您将一次又一次地看到一些建议：使用Aperture Priority模式进行拍摄。 那么，为什么有那么多专业摄影师喜欢Aperture Priority？ 是什么让它如此好？ 让我们找出答案。

Aperture Priority mode (Av or A on the mode dial) is one of the two semi-automatic modes your camera has. The other is Shutter Speed Priority (Tv or S on the mode dial). In Aperture Priority mode, you set the aperture and ISO while your camera automatically sets the shutter speed based on its light meter reading. In Shutter Speed Priority mode, you set the shutter speed and ISO, your camera sets the aperture.

光圈优先模式(模式拨盘上的Av或A)是相机具有的两种半自动模式之一。 另一个是快门速度优先(模式拨盘上的Tv或S)。 在光圈优先模式下，您可以设置光圈和ISO，而相机会根据照度计读数自动设置快门速度。 在“快门速度优先”模式下，可以设置快门速度和ISO，相机可以设置光圈。

With Aperture Priority mode, you don’t give up control over how your images look. If your camera is picking a shutter speed that overexposes or underexposes the scene, you use exposure compensation to adjust it without having to worry about selecting an exact shutter speed.

使用“光圈优先”模式，您不会放弃对图像外观的控制。 如果相机选择的快门速度曝光过度或曝光不足，则可以使用曝光补偿进行调整，而不必担心选择确切的快门速度。

Now, let’s look at why it’s great.

现在，让我们看看它为什么很棒。

光圈控制事物的外观 (Aperture Controls How Things Look)

Aperture is one of the most important factors in how things appear in your images since it’s what controls the depth of field. If you use a wide aperture, like f/1.8, you’ll have a narrow depth of field with only a small area of the image in focus and a nice blurry background.

光圈是影响事物在图像中呈现方式的最重要因素之一，因为它是控制景深的因素。 如果您使用较大的光圈(例如f / 1.8)，则景深较窄，只有一小部分图像清晰对焦，并且背景模糊。

On the other hand, if you use a narrow aperture like f/16, you’ll have a really wide depth of field with almost everything sharp.

另一方面，如果您使用f / 16之类的窄光圈，则景深非常大，几乎所有东西都清晰。

I shot both the images above with the same 85mm lens, but they’re drastically different, in part due to the aperture. I just couldn’t have shot the portrait well at f/16 or the skyline at f/1.8.

我用相同的85mm镜头拍摄了上面的两个图像，但是它们完全不同，部分是由于光圈。 我只是无法在f / 16上拍摄出好的人像或在f / 1.8下拍摄出天际线。

Whatever lens you’re using, the aperture you use is going to be a big part of how the final photo looks. Shutter speed—which we’ll look at next—matters, of course, but not as much as the aperture in most situations.

无论使用哪种镜头，使用的光圈都将成为最终照片外观的重要组成部分。 当然，快门速度(我们将在后面讨论)非常重要，但在大多数情况下，快门速度并不比光圈大。

快门速度对变化不太敏感(在手持速度下) (Shutter Speed Is Less Sensitive to Change (At Handheld Speeds))

Shutter speed falls into two broad categories: fast enough to use your camera handheld or slow enough to blur motion. The general rule is that if you’re not using image stabilization, the slowest shutter speed you can reliably use is 1/[the focal length of the lens, accounting for crop factor] of a second. In other words, if you’re using a 100mm lens, your slowest handheld shutter speed is 1/100th of a second; if you’re using a 50mm lens, it’s 1/50th of a second.

快门速度分为两大类：足够快以使用手持式相机或足够慢以使运动模糊。 一般规则是，如果不使用图像稳定功能，则可以可靠使用的最低快门速度为1 / [镜头的焦距，占裁切因数]。 换句话说，如果您使用100mm镜头，则最慢的手持快门速度为1/100秒； 如果您使用50mm镜头，则为1/50秒。

Unless you’re shooting really fast moving subjects, the difference between 1/100th of a second and 1/4000th of a second just doesn’t matter too much to the overall look of things. That’s a 6-stop difference; the aperture equivalent is going from f/1.8 to f/14. The photo above was shot at 1/125th of a second; the one below was shot at 1/1600th of a second; can you spot the difference?

除非您要拍摄快速移动的主体，否则1/100秒和1/4000秒之间的差异对于事物的整体外观来说并没有太大关系。 那是6站的差距； 等效光圈从f / 1.8变为f / 14。 上面的照片以1/125秒的速度拍摄； 下面的一个以1/1600秒的速度拍摄； 您看得出来差别吗？

This is why Aperture Priority mode is so much more useful than Shutter Speed Priority mode. For shutter speed to really affect how your image looks, you need to slow down and use a tripod, in which case, you’re probably going to use Manual mode. To take both photos above, I just put my camera in Aperture Priority mode at f/1.8; the camera chose an appropriate shutter speed. As long as it doesn’t drop too low—in which case increase your ISO—you’re going to come away with good shots reliably.

这就是为什么光圈优先模式比快门速度优先模式有用得多的原因。 为了使快门速度真正影响图像的外观，您需要放慢速度并使用三脚架，在这种情况下，您可能会使用手动模式。 要同时拍摄上述两张照片，我只是将相机置于光圈优先模式下(f / 1.8)； 相机选择了合适的快门速度。 只要它不会降得太低(在这种情况下增加ISO) ，您就会可靠地获得出色的拍摄效果。

它使您保持灵活 (It Keeps You Flexible)

Manual mode is great for consistency. You can dial in your settings and know that each photo is going to be identically exposed—assuming nothing changes in the scene. It is, however, inherently inflexible. If something changes, you have to adjust everything.

手动模式非常适合保持一致性。 您可以拨入您的设置，并知道每张照片都将被相同地曝光-假定场景中没有任何变化。 但是，它本质上是不灵活的。 如果有什么变化，您必须进行所有调整。

Aperture Priority mode, on the other hand, is incredibly flexible. You can go from shooting a close up portrait at f/1.8 to shooting a group shot at f/8 with a single dial twist. If you’re doing street photography, you can go from dark alleys to bright plazas and not have to change a thing. If your shutter speed ever drops too low, all you have to do is increase your ISO—something that takes seconds—to keep the quality of your shots high. Similarly, if your camera starts underexposing or overexposing, you can tweak the exposure compensation and keep going.

另一方面，光圈优先模式非常灵活。 您可以从以f / 1.8拍摄特写人像到通过单拨盘拍摄以f / 8拍摄团体照。 如果您要进行街头摄影，则可以从黑暗的小巷到明亮的广场，而不必进行任何更改。 如果您的快门速度降得太低，那么您要做的就是增加ISO(需要几秒钟的时间)，以保持较高的拍摄质量。 同样，如果您的相机开始曝光不足或曝光过度，则可以调整曝光补偿并继续拍摄。

When we advocate manually controlling your camera here on How-To Geek, using Aperture Priority mode like this is what we’re talking about. You don’t have to enter every single setting by hand, but you should understand what your camera is doing at any given time, and have things set up in such a way that you control how the final image looks. If shutter speed doesn’t matter, then let your camera pick it. And when it’s picking the wrong one, all you have to do is adjust the ISO or exposure compensation.

当我们在此处建议如何通过“如何控制极客”来手动控制您的相机时，我们正在使用这样的Aperture Priority模式。 您不必手动输入每个设置，但您应该了解相机在任何给定时间的工作，并以控制最终图像外观的方式进行设置。 如果快门速度无关紧要，请让相机选择。 当选择了错误的时，您要做的就是调整ISO或曝光补偿。

翻译自: https://www.howtogeek.com/398532/why-is-aperture-priority-mode-so-good/

p光圈和dc光圈的区别