长时间曝光计算_如何拍摄好长时间曝光的照片

长时间曝光计算

In long exposure photography, you take a picture with a slow shutter speed—generally somewhere between five and sixty seconds—so that any movement in the scene gets blurred. It’s a way to show the passage of time in a single image. Let’s look at how to do them right.

在长时间曝光摄影中，您以较低的快门速度(通常在5到60秒之间的某个时间)拍摄照片，从而使场景中的任何运动都变得模糊。这是在单个图像中显示时间流逝的一种方式。让我们看看如何正确地做它们。

Long exposure photography is all about showing movement and time passing in a single photo; it’s one of the ways you can show motion in still images. While you can use long exposure times to take photos of subjects that you want to stay still—such as the night sky—these aren’t strictly long exposure images because, unless you’re deliberately shooting star trails, they don’t show motion.

长时间曝光摄影就是要在单张照片中显示运动和时间。这是您可以在静止图像中显示运动的一种方式。虽然您可以使用较长的曝光时间来拍摄想要保持静止的物体(例如夜空)的照片，但这些图像并不是严格的长时间曝光图像，因为除非您故意拍摄星迹，否则它们不会显示运动。

The classic examples—and some of the most popular long exposure subjects—are photos of bodies of water like the sea or waterfalls. Look at the long exposure image below. I’ve used a shutter speed of 10 seconds to blur and smooth the water and clouds, giving them an ethereal quality. This is the long exposure look.

典型的例子(以及一些最受欢迎的长时间曝光的对象)是诸如大海或瀑布之类的水体的照片。请看下面的长时间曝光图像。我使用10秒的快门速度来模糊和平滑水和云，从而赋予它们空灵的品质。这是长时间曝光的外观。

I took the next shot about ten minutes later. I’ve used a shutter speed of 1/100th of a second here, and you can see that the water and clouds look very different from the long exposure shot above.

大约十分钟后，我拍摄了下一张照片。我在这里使用的快门速度为1/100秒，您可以看到水和云看起来与上面的长时间曝光截然不同。

技术资料 (The Technical Stuff)

For a long exposure image, you’re really only after one thing: a slow shutter speed. You’ll start to get the long exposure look at around half a second for fast moving subjects, but generally, you’ll want a shutter speed of between ten and thirty seconds. For some photos, you might even want to go much longer. Every other decision you make will be in service to this goal.

对于长时间曝光的图像，您实际上只需要一件事：较低的快门速度。对于快速移动的拍摄对象，您将开始获得大约半秒钟的长时间曝光，但是通常，您希望快门速度在10到30秒之间。对于某些照片，您甚至可能想走更长的时间。您做出的所有其他决定都将有助于实现这一目标。

A tripod is essential. Without one, you won’t be able to get sharp pictures at slow shutter speeds. So don’t leave home without your tripod.

三脚架必不可少。没有一个，您将无法在低快门速度下获得清晰的图像。所以不要在没有三脚架的情况下离开家。

Unless you have a compelling reason not to, always set your ISO to the camera’s native setting. For almost all cameras, that’s 100. This gives you the slowest shutter speeds and the highest quality images.

除非您有令人信服的理由，否则请始终将ISO设置为相机的本机设置。对于几乎所有相机来说，都是100。这使您拥有最慢的快门速度和最高质量的图像。

Aperture is a little trickier to set. With most lenses, you’ll start to see a drop in image quality after around f/18. Around f/16 is normally considered to offer the best balance between a slow shutter speed and a sharp image so it’s the best starting place for long exposure images. You normally want a large depth of field anyway.

光圈设置有些棘手。对于大多数镜头，f / 18左右后，您会开始发现图像质量下降。通常认为f / 16左右可在慢快门速度和清晰图像之间提供最佳平衡，因此它是长时间曝光图像的最佳起点。无论如何，您通常都希望有较大的景深。

If you’ve set your ISO to 100 and the aperture to f/16 and you still aren’t getting a slow enough shutter speed for the shot you want, you should consider using a neutral density filter instead of a tighter aperture or low ISO mode. Neutral density filters go in front of the lens and block between one and ten stops of light from entering the camera. For example, if you get a proper exposure with a shutter speed of one second without a ND filter, adding a three stop filter will take the shutter speed needed for a proper exposure to eight seconds; a six stop filter will take it to 64 seconds.

如果您已将ISO设置为100，并将光圈设置为f / 16，但仍无法获得足够慢的快门速度以进行所需的拍摄，则应考虑使用中性密度滤镜，而不是使用更窄的光圈或较低的ISO模式。中性密度滤光片进入镜头前，并阻挡一到十个光阑进入相机。例如，如果您在不使用ND滤镜的情况下以1秒的快门速度进行了适当的曝光，则添加三档滤镜将使正确曝光所需的快门速度达到8秒；一个六档过滤器将使它达到64秒。

Most cameras have a maximum shutter speed of thirty seconds. If you want to go beyond this, you’ll need to use Bulb mode and time the exposure yourself.

大多数相机的最大快门速度为三十秒。如果您想超越此范围，则需要使用Bulb模式并自行设置曝光时间。

其他技巧 (Other Tips and Tricks)

The best time to take long exposure photos are in the hours around sunrise and sunset. Not only do you get great light, but since there’s less of it, it’s easier to have slower shutter speeds. You can take long exposure shots at midday, but you’ll need to stack the ND filters.

长时间曝光照片的最佳时间是在日出和日落之间。您不仅会获得优质的光线，而且由于光线较少，因此快门速度较慢也更容易。您可以在中午进行长时间曝光拍摄，但是您需要堆叠ND滤镜。

The longer the exposure time, the more things will blur and the less texture and definition you’ll have in the moving areas of the image. You always need to find the right balance for the look you’re after. One day last year, I went to shoot waves breaking over a local pier. I originally started with a shutter speed of eight seconds and this was the result. It’s not great.

曝光时间越长，模糊的事物越多，并且在图像的移动区域中所具有的纹理和清晰度就越低。您始终需要为想要的外观找到合适的平衡。去年的一天，我去拍摄海浪拍打着当地的码头。我最初以八秒的快门速度开始，这就是结果。不好

I was dramatically over estimating how long a shutter speed I wanted for the image I had in mind. Here’s a shot I took at 1/5th of a second. Much better.

我对于估算想要的图像需要多长时间的快门速度感到震惊。这是我在1/5秒内拍摄的照片。好多了。

Play around with different subjects. Water is one of the simplest and can lead to stunning results, but anything that moves can work. Bright objects that move at night—like cars or ferris wheels—are another easy starting place that look great.

玩弄不同的主题。水是最简单的水之一，可以带来惊人的效果，但是任何移动的东西都可以起作用。夜间移动的明亮物体(例如汽车或摩天轮)是另一个容易看起的好地方。

Long exposure images work best when you have something moving contrasted with something totally stationary. This is why they’re so popular with landscape photographers. While the water looks cool in all the photos in this article, if it wasn’t for the rocks or landscapes, it would just look like a blurry mess.

当您将移动的物体与完全静止的物体形成对比时，长时间曝光的图像效果最佳。这就是为什么它们在风景摄影师中如此受欢迎的原因。尽管本文中所有照片中的水看起来都很酷，但是如果不是岩石或风景，那看起来就像是一片混乱。

Since you have to slow down anyway to take long exposure images, they’re a great time to put serious thought into composition. You can also use them as an opportunity to play around with limited color palettes.

由于无论如何您都必须放慢速度才能拍摄长时间曝光的图像，因此这是个认真思考构图的好时机。您也可以利用它们作为机会来使用有限的调色板。

Long exposure images are incredibly rewarding. They’re one of the few areas of photography where smartphone cameras just can’t compete. Most long exposure images are also landscapes, so be sure to check out our guide to great landscape photos as well.

长时间曝光的图像令人难以置信。它们是智能手机相机无法竞争的少数摄影领域之一。大多数长时间曝光的图像也是风景，因此也请务必查看我们有关风景照片的指南。

Image Credits: Giancarlo Revolledo, Sebastian Davenport-Handley via Unsplash.

图片来源： Giancarlo Revolledo ，塞巴斯蒂安·达文波特·汉德利，摄于Unsplash。