Fixed focal length lenses are one of the key limitations of smartphone cameras. So it’s no surprise that add-on lenses, which allow you to vary the focal length, are among the most popular smartphone accessories.

We have had the chance to test one of the more extreme variants, the Apexel 8mm fisheye lens, which provides a whopping 238-degree field-of-view. The lens comes with a clip that makes it very easy and quick to attach to most mobile devices – Apexel claims it is compatible with 98% of all smartphones – but we’ve found it to work best with the latest generation Apple iPhones, as the back of the lens slots onto the iPhone’s lens protrusion, where it is firmly held in place. On other devices, without a protruding camera-module, things can get a little more difficult and you might have to optimize the position of the lens by moving it around very slightly until you find a position that gives the best image quality.
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Read full post here:
https://www.dpreview.com/articles/8491327862/apexel-8mm-fisheye-lens-for-smartphones