成像锐利是什么意思

In photography, we strive to take “sharp” photos. Generally, this means that you want the subject to be in focus with clear lines, crisp details, and no (unintended) blurring. It’s a combination of accurate focus, a static camera, and the properties of the lens you’re using.

在摄影中，我们努力拍摄“清晰”的照片。 通常，这意味着您希望主体清晰，线条清晰，细节清晰，并且没有(意外)模糊。 它是准确对焦，静态相机和所用镜头的属性的组合。

One thing to note is that there are two kinds of sharpness: there’s an official optical measure (it’s called acutance) that gets all kinds of complicated fast, and there’s perceived sharpness, which is what photographers mostly want. We’re tackling the latter one today, although there is some overlap with optical sharpness.

需要注意的一件事是，锐度有两种：一种是官方的光学度量(称为锐度)，它可以使各种复杂的物体快速变快；另一种是锐利的，这正是摄影师最想要的。 我们今天要解决的是后者，尽管在光学锐度方面存在一些重叠。

So, let’s dig in.

所以，让我们深入。

什么是清晰度？ (What is Sharpness Anyway?)

As defined above, a sharp image is one where the subject of the image—or the bits of the subject you want—are in perfect focus with every detail crisp and clean. Below, is one of my favorite examples of this.

如上所定义，清晰的图像是图像的主体(或您想要的主体的一部分)完全聚焦而每个细节都清晰，清晰的图像。 下面是我最喜欢的示例之一。

The main “subject” of the photo is Kat’s eyes; they’re so sharp you can see the individual eyelashes even though the focus fades off across her face. Just compare the sharpness of her eyes to the slight blur of her ears and the indistinct background. I know I’m tooting my own horn, but it’s a pretty great example of the classic “portrait look.”

照片的主要“主题”是Kat的眼睛； 它们是如此的锋利，即使焦点从她的脸上逐渐消失，您也可以看到各个睫毛。 只需将她的眼睛的清晰度与耳朵的轻微模糊和模糊的背景进行比较即可。 我知道我在吹牛角，但这是经典“ 肖像 ”的一个很好的例子。

Let’s look at another example, this time from landscapes.

让我们来看另一个例子，这次是从风景中。

Here the image is sharp throughout the frame, from the rocks in the foreground to the lighthouse in the background. The motion blur in the rocks is just an element of long exposure photography.

从前景中的岩石到背景中的灯塔，整个画面中的图像都是清晰的。 岩石中的运动模糊只是长时间曝光摄影的一个要素 。

In both examples above, the sharpness is a result of accurate focus, a static camera, and the lens and its settings. Let’s take them one by one.

在以上两个示例中，清晰度都是精确对焦，静态照相机以及镜头及其设置的结果。 让我们一一介绍。

准确聚焦 (Accurate Focus)

Accurate focus is arguably the most important factor in taking sharp images. If you miss focus, even by a small amount, something will look off with your image and no amount of work in post will save it. I love the photo below of an old man setting up his fishing gear, but I missed the focus.

准确对焦可以说是拍摄清晰图像时最重要的因素。 如果您错过焦点，即使只是少量，也会使您的图像看起来有些模糊，并且后期的工作也不会保存它。 我喜欢下面一个老人在设置他的渔具的照片，但我错过了焦点。

Even though I was only off by a little bit—somewhere between his hands and his sweater is where the focus rests—the photo is now pretty much unusable for anything but teaching people not to miss focus.

即使我只有一点点距离-他的手和他的毛衣之间的某个地方就是焦点所在-现在，这张照片几乎是无用的，只能教人们不要错过焦点。

Compare the image to the photo of Kat above. A lot more of that image is blurry but because her eyes are sharp the image works. Here, although the rest of the subject is pretty much in focus, the fisherman’s face isn’t, and the photo doesn’t work.

将图像与上面的Kat的照片进行比较。 该图像更多是模糊的，但由于她的眼睛清晰，该图像有效。 在这里，尽管其余主题几乎都清晰可见，但渔夫的脸却没有，照片也无法工作。

静态相机 (A Static Camera)

For a sharp image, there can be no camera movement in the image. This means one of two things: either you shoot with a fast enough shutter speed to freeze motion or you use a tripod to lock your camera down.

对于清晰的图像，图像中不能有相机运动。 这意味着两件事之一：要么以足够快的快门速度进行拍摄以冻结运动，要么使用三脚架将相机锁定下来 。

Which option you use depends on what sort of photograph you’re trying to take. For a portrait, you’ll need to use a fast shutter speed. For a landscape, you can either go with a fast shutter speed or a tripod if you want to use a longer exposure time.

您使用哪种选项取决于您要拍摄的照片种类。 对于人像，您需要使用较快的快门速度。 对于风景，如果要使用更长的曝光时间，则可以使用较快的快门速度，也可以使用三脚架。

您正在使用的镜头的属性 (The Properties of the Lens You’re Using)

Lenses are far more important than your camera when it comes to image quality. Even the most basic of DSLRs can take great, sharp photos while a bad lens will render ten grand worth of camera worthless.

在图像质量方面， 镜头比相机重要得多 。 即使是最基本的数码单反相机，也可以拍摄出清晰锐利的照片，而不良的镜头则会使十台价值不菲的相机毫无价值。

In general, good lenses—which means expensive lenses—deliver greater sharpness throughout the image, referred to by photographers as “edge-to-edge sharpness.” Cheaper lenses will probably take images where the center of the image is sharp, but the edges are blurry.

通常，优质的镜头(即昂贵的镜头)可在整个图像中提供更高的清晰度，被摄影师称为“边缘到边缘的清晰度”。 较便宜的镜头可能会在图像中心较锐利但边缘模糊的情况下拍摄图像。

Better lenses also have less optical distortion or chromatic aberration. You can see a small loss of edge sharpness in the image below of a newspaper. The block of text on the left is from the center of the image while the block on the right is from the edge. I used a Canon 50mm f/1.8 for this test.

更好的镜头还具有较小的光学畸变或色差 。 在报纸下面的图像中，您可以看到边缘清晰度的少量损失。 左侧的文本块是从图像的中心开始，而右侧的文本块是从边缘开始。 我为此测试使用了佳能50mm f / 1.8。

Lenses don’t have the same quality throughout their whole range, which can make matters even more confusing. Most lenses have a “sweet spot” aperture where they’re at their sharpest. It’s normally at some point between f/5.6 and f/16 depending on how the lens is designed.

镜头在整个范围内的质量都不一样，这会使事情变得更加混乱。 大多数镜头在最清晰的地方都有一个“最佳点” 光圈 。 根据镜头的设计，通常在f / 5.6至f / 16之间。

To get an idea of how sharp the lenses you shoot with are and when they’re at their best, check out the reviews on DxOMark.

要了解所拍摄镜头的清晰度以及何时达到最佳状态， 请查看DxOMark上的评论 。

So there you have it: sharpness is focus plus a decent lens—so long as you don’t fumble your camera while taking the shot.

这样就可以做到：锐度就是对焦加上一个不错的镜头-只要您在拍摄时不会弄乱相机。

翻译自: https://www.howtogeek.com/393080/what-does-it-mean-for-a-photo-to-be-“sharp”/

成像锐利是什么意思