What are Porro prism binoculars and roof prism binoculars?

Roof prism, Porro prism (and reversed Porro prism) binoculars each use image-erecting prisms to provide correctly oriented images. You will recognize the Porro prism as a "traditional" binocular design with offset prisms while the roof prism binocular has parallel barrels and a more streamlined appearance. The size, design and quality of the prisms used in the binocular design affect what you see and how clearly an image appears across your viewing area. You may prefer one binocular over another because of the design.

Porro Prism Binoculars
Porro Prism models will deliver the best optics for the dollar, but lack the durability and compact styling of roof prism models.

Reversed Porro Prism Binoculars
This design allows for a compact binocular that easily fits in your hand.

Roof Prism Binoculars
Roof Prism models will deliver more durability but you will need to spend more money to get good optical quality in this design.

List of common binocular questions.




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