Alexanian hand drills and polishes each hole in the frame and imparts a brushed matte finish on the rims around the lenses.

Are these high-quality yet relatively lightweight image-stabilized binoculars worth looking into for wobble-free viewing over ...

\(power \ of \ a \ lens \ (D) = \frac{1}{focal \ length \ (m)}\) A lens has a power of -3.33 dioptres. Calculate the focal length and state what type of lens it is.