Iphone5 camera gray does not affect

It is easy to understand from the perspective of photography: because the mobile phone uses a large aperture, such as F2, F2.8 If the SLR shoots with this large aperture, the dust on the lens will not appear, which has no effect on the photo! If you use a small aperture, such as F 1 1, 22, F32, you can see dust, but the camera of the mobile phone can't reach such a small aperture.

Aperture, like a pinhole imaging hole. The smaller the hole, the clearer what you can see through it; The bigger the hole, the more blurred what you see. So when the aperture is small, dust will obviously appear in the photo.

This is why there is dust in the camera of the mobile phone, but there are no black spots and dust in the photo.