The 50mm lens continues to be a favourite, but not always for the same reason.

There are in fact four reasons people often say they like a 50mm lens:

1. On a full frame camera, it has the width of view that our eyes see sharply. This gives it a natural look: no compressed perspective (telephoto lens), and no expanded perspective (wide angle lens).
2. Or – on a crop camera, it is a 75/80mm lens, which makes it a great portrait lens.
3. And most 50mm lenses are fast. Meaning a low “f-number”, meaning a wide aperture, meaning selective depth of field.
4. And finally, that also gives you a nice fast shutter speed in low light without having to go to very high ISO values.

Those last two points are illustrated by this picture, 50mm at f/1.2:

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