For my 8-inch, whose aperture in metric units is 203 mm, the focal ratio is f/10. Another example is my 106mm f/5 refractor, whose focal length is 106 × 5 = 530 mm.

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The Viltrox AF 16mm f/1.8 FE is an impressive ultra-wide-angle prime lens that offers pro-grade performance and image quality at an affordable price.

A long focal length is basically a telephoto camera and a short focal length is used for ultrawide cameras. In the Samsung Galaxy S24 Ultra, the primary camera has a 24mm focal length.

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The GS61 shares many specs with the now-discontinued Zenith Star 61, including focal length, aperture, and diameter, as well as the FPL53 ED doublet lens for high-contrast images.

Let's talk about two more camera terms before we move on: focal length and aperture. Focal length is specified in millimeters. The bigger the number, the more zoomed in the lens can go.

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Aperture and focal length will affect the depth of field, so different combinations of aperture and focal length will produce different hyperfocal distances.

The smaller the value, the higher the aperture. Most kit lenses offer a range of f/3.5 to f/5.6, where the aperture dynamically shifts between the widest and zoomed-in focal lengths.

Focal length is measured in millimeters (mm). As you might expect, a telephoto camera tends to have a longer focal length (hence why we've started using periscope telephoto lenses since no one ...