LENSES: Magnifying glass come with 4 replaceable lens at 1.5X, 2.0X, 2.5X, 3.5X maginification,Each lenses are different totally. 1.5X power at 333mm focal length, 2.0X power at 250mm focal length ...

For landscape astrophotography, start with a lens with a focal length of between 50-100mm lens. This will produce an image with a mid-focal length and depth of field to resolve details on the ...

A stand fan is an essential cooling device whose ... delivers efficient cooling with its 1400 RPM speed and 400mm sweep length. Designed for silent operation, it ensures a noise-free environment ...

WASHINGTON, D.C. — On a sunny afternoon steps from the Lincoln Memorial, crowds of protesters gathered to stand up for science. Wispy clouds streaked across blue skies as people chanted ...

Readers help support Windows Report. We may get a commission if you buy through our links. Wondering how to use the magnifier in Windows 10? The steps are simple. Windows 10 has accessibility tools ...

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