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What Is the Corelation Between Distance & the Optical Lens of Binoculars?

Magnification of binoculars can also be expressed as their distance, or how much closer the subject appears to be. Binoculars achieve their magnification by using lenses on the outside of the frame and multiple lenses on the inside.

Number Specifications
- The correlation between distance (magnification) and the optical lenses can be measured by the number specifications of binoculars. The devices usually have two sets of numbers which define them, such as 7 by 32 or 8 by 40. The first number measures the strength of magnification, and the second number is the objective lens size in millimeters. A larger objective lens means more light and a better viewing experience.
Prisms
- Many modern binoculars use prisms, blocks of glass that work as mirrors, and they bend light and help with magnification. Binoculars with prisms can be powerful with good clarity even if their size is relatively small.
Coated Lenses
- Lenses that are coated help to remove glare and increase light levels entering the optics. Binoculars that are more expensive will have a higher quality of coating and use this finish on more of the lenses within the device.

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