五棱镜和五面镜用在单反相机的取景器上。
五棱镜是五面反射的棱镜,将光束转变90度。
Pentaprism and pentamirror are used in the viewfinder systems of single-lens reflex cameras.
A pentaprism is a five-sided reflecting prism used to deviate a beam of light by 90°.
五面镜是用在较便宜的单反相机的取景器上,使成像上下与左右均倒置。
Pentamirror is the optical device used in the viewfinder systems of cheaper single-lens reflex cameras instead of the pentaprism. It is used to reverse again the upside-down and laterally reversed image coming from the reflex mirror.
五面镜不是用一整个玻璃棱镜,而是用3块镜子来达到相同的目的。五面镜更便宜更轻,但是成像的质量和亮度差。
|
五棱镜 |
五面镜 |
Canon |
xD xxD |
xxxD xxxxD |
Nikon |
D70 及更高 |
D60 及以下, D5000 |
Instead of the solid block of glass of the prism in pentaprism system, here 3 simple mirrors are used to perform the same task. This is cheaper and lighter, but generally produces a viewfinder image of lower quality and brightness.
|
pentaprism |
pentamirror |
Canon |
xD xxD |
xxxD xxxxD |
Nikon |
D70 and upper |
D60 and lower, D5000 |
并不是比较谁好谁差,清理灰尘的备忘录