Porro Or Roof Prism Astronomy
The prims are in the shape of a right angled triangle and they reflect the light rays through the binoculars so you see your image clearly.
Porro or roof prism astronomy. The pentax sp series of porro prism binoculars is characterised by an unusual focusing mechanism. Porro prism includes two right angled prisms that are facing each other. There are a few reasons for this but it is mainly due to the way a roof prism still corrects the inverted image as a porro prism does but the light enters and then passes out of the prism in the same plane straight through light path meaning the designers can make a more compact and streamlined shape of binocular. However porro prism binoculars are great watching birds or other small objects.
Roof prism binoculars have lately become more popular than porro prism binoculars. If you are traveling with your binoculars roof binoculars will be a better choice than porro prism binoculars because they are designed to be a lot more durable and are usually waterproof. It also allows them to incorporate an enormously useful feature. Contain 2 prisms called dach or dachkanten prism and derive their name from abbe koenig ak prism design.
Most binoculars marketed for astronomy use porro prisms named for the italian optician who invented them in the 1850s. That is why we called it porro prism. Roof prism units are smaller and lighter weight but have a more complicated touchy optical design which makes them more difficult and expensive to manufacture well. Porro prism is made to increase the light in its path and increase the magnification so that we can get a clear bright image.
Roof binoculars are in a higher general price category than porro prism binoculars and represent a class of more powerful viewing instruments. These are easy to hold for you are more compact and more expensive than porro prism binoculars. Roof prism binocular is more streamlined as the glasses are in line with one another. To learn more about astronomy please visit orion resource center where you can find articles images videos and more.
Gone is the familiar eyepiece bridge because all the workings are internal aiding with waterproofing. Porro prisms are the more traditional ones and these are seen in older binoculars with a zig zag shape.