Bushnell Powerview 10x50mm Black Porro Prism Binoculars For binoculars, the optical diameter (also known as objective lens diameter) is the size of each of the front-facing objective lenses of a binocular measured in millimeters Binoculars with larger objective lenses collect more light, which increases image resolution and brightness
Meade ACF 0. 68x Focal Reducer with 50mm T-thread Adapter - binoculars. com Introduction: The Meade 0 68x focal reducer is designed for use with Me- ade’s Advanced Coma-Free (ACF) telescopes, of any aperture, using the 2”-24 (2” diameter, 24 threads per inch) rear cell thread This rear cell thread is standard on all Meade ACF tele - scopes The 0 68x focal reducer consists of 4 lenses in 2 groups with all air-to-glass surfaces fully multi-coated with broadband
Orion BX90 90mm Equatorial Refractor Instruction Manual - binoculars. com Congratulations on your purchase of an Orion telescope Your new BX90 Equatorial Refractor is a terrific starter instrument for exploring the exotic wonders of the night sky Designed to provide a wide field of view and excellent portability, it will provide many hours of enjoyment for the whole family