focal length

简明释义

焦距透镜的)焦距

英英释义

例句

1.When you increase the focal length, the subject appears larger in the frame.

当你增加焦距时，主题在画面中显得更大。

2.The focal length of this lens is 50mm, making it ideal for portrait photography.

这个镜头的焦距是50毫米，非常适合人像摄影。

3.The focal length can greatly affect the depth of field in your images.

镜头的焦距会极大影响你图像的景深。

4.A shorter focal length allows for a wider field of view, perfect for landscape shots.

较短的焦距允许更宽的视野，非常适合拍摄风景。

5.To capture distant subjects, use a lens with a longer focal length.

要拍摄远处的主题，请使用具有较长焦距的镜头。

作文

In the world of photography and optics, the term focal length refers to the distance between the lens and the image sensor when the subject is in focus. This measurement, typically expressed in millimeters (mm), plays a crucial role in determining how much of a scene will be captured in an image and how large the subject will appear. Understanding focal length is essential for photographers and videographers as it influences not only the composition of their shots but also the overall aesthetic of the images they create.The focal length of a lens can significantly affect the perspective and depth of field in a photograph. For example, a lens with a short focal length, such as 18mm, allows for a wider field of view, making it ideal for capturing landscapes or large groups of people. This wide-angle perspective can create a sense of depth and space, making the viewer feel as though they are part of the scene. However, one must be cautious with wide-angle lenses, as they can also introduce distortion, particularly at the edges of the frame.On the other hand, a lens with a long focal length, like 200mm, provides a narrower field of view and magnifies distant subjects. This is particularly useful for wildlife photography or sports events, where the photographer needs to capture subjects from a distance without disturbing them. Longer focal lengths also compress the background, which can create a pleasing bokeh effect, isolating the subject from its surroundings.Moreover, the focal length also affects the depth of field, which refers to the range of distance within a photo that appears acceptably sharp. Lenses with shorter focal lengths tend to have a greater depth of field, allowing more of the scene to be in focus, while longer focal lengths usually result in a shallower depth of field, emphasizing the subject and blurring the background. This technique is often employed in portrait photography to draw attention to the subject’s face while softly fading away distracting elements in the background.In addition to these technical aspects, understanding focal length can also enhance a photographer's creative vision. By experimenting with different lenses and their respective focal lengths, photographers can develop their unique style and approach to storytelling through imagery. For instance, using a fish-eye lens, which has an extremely short focal length, can produce surreal, distorted images that challenge conventional perceptions of space and perspective.In conclusion, the concept of focal length is fundamental to mastering photography and videography. It influences not only the composition and clarity of an image but also the emotional impact it can generate. By understanding how focal length works and experimenting with various lenses, photographers can unlock new creative possibilities and elevate their work to new heights. Whether capturing vast landscapes or intimate portraits, the choice of focal length can make all the difference in achieving the desired outcome in visual storytelling.

在摄影和光学的世界中，术语焦距指的是镜头与图像传感器之间的距离，当主题处于对焦状态时。这一测量通常以毫米（mm）表示，在确定图像中将捕捉到多少场景以及主题将呈现多大方面起着至关重要的作用。理解焦距对于摄影师和摄像师来说是必不可少的，因为它不仅影响他们拍摄的构图，还影响他们创作的图像的整体美感。镜头的焦距可以显著影响照片中的透视和景深。例如，短焦距的镜头，如18mm，允许更宽的视野，非常适合拍摄风景或大型人群。这种广角透视可以创造出深度和空间感，使观众感到自己是场景的一部分。然而，使用广角镜头时必须小心，因为它们也可能在画面的边缘引入失真。另一方面，长焦距的镜头，如200mm，提供更窄的视野并放大远处的主题。这在野生动物摄影或体育赛事中尤为有用，摄影师需要在不打扰对象的情况下从远处捕捉主题。较长的焦距还会压缩背景，这可以创造出令人愉悦的散景效果，将主题与周围环境隔离开来。此外，焦距还影响景深，景深是指照片中看起来清晰的距离范围。短焦距的镜头往往具有更大的景深，允许更多场景保持对焦，而长焦距的镜头通常会导致较浅的景深，强调主题并模糊背景。这种技术常常用于人像摄影，以吸引观众的注意力集中在主题的面孔上，同时柔和地淡化背景中分散注意力的元素。除了这些技术方面，理解焦距还可以增强摄影师的创意视野。通过尝试不同的镜头及其各自的焦距，摄影师可以发展出独特的风格和叙事方式。例如，使用鱼眼镜头，其焦距极短，可以产生超现实的失真图像，挑战对空间和透视的传统认知。总之，焦距的概念是掌握摄影和摄像的基础。它不仅影响图像的构图和清晰度，还影响它能产生的情感冲击。通过理解焦距的工作原理并尝试各种镜头，摄影师可以解锁新的创意可能性，将他们的作品提升到新的高度。无论是捕捉广阔的风景还是亲密的人像，焦距的选择都可以在实现视觉叙事的预期结果中发挥重要作用。