I have an iPhone X, with a camera specs of:

  • Wide-angle: ƒ/1.8 aperture
  • Telephoto: ƒ/2.4 aperture

Why does the phone need software to produce Portrait Mode image (image with background blur / bokeh)? With my SLR camera, shooting with f2.4 and definitely f1.8 apertures are more than enough for a blurred background.

  • Could it be because there actually is no (adjustable) aperture? I suspect that all exposure and focus control is software/electronic in phone cameras. Could be wrong, but I know there's no mechanical aperture in the phone cameras (including iphone) that I've had.
    – user8356
    Jun 7 '21 at 20:01
  • With your SLR, the lenses are almost certainly much longer (actual) focal lengths than your smartphone in order to provide similar fields of view for the widely disparate sensor sizes.
    – Michael C
    Jun 7 '21 at 22:40