iPhone 7+/8+ photographers - 2x may not mean what you think

Photographers using the iPhone 7+ or 8+ know it has two lenses, one wide-angle and one telephoto.

What you may not know is that quite often, tapping the "2x" button on the Camera screen will not actually use the telephoto lens, it will digitally zoom the wide angle lens (with associated digital effects upon resolution.)

You can verify this yourself - the telephoto is the "inside" lens of the two. Go into an area that is very brightly lit and cover the inner lens with your finger, and you will see the image is blocked.

Now go into a slightly less brightly lit area and you will find your finger is not obstructing the camera lens at all - because it is digitally zooming the wide-angle lens.

This is because the wide-angle lens is the more light sensitive of the two (f/1.8 for the wide-angle, f/2.8 for the telephoto), and the software will prefer using the wide-angle lens in anything but brightly-lit environments as it assumes digital zoom and the wide-angle lens will result in a "better" photo.

However the digital zoom also makes the resulting photo largely useless for anything but screen-size reproduction; you can easily see the difference if you zoom in only slightly.

This isn't a big deal for most, but for those shooting for print or other purposes, you may want to verify using the finger method before taking any "important" photos at 2x zoom.