It might have noticed not everyone, but the new Samsung Galaxy S4 has a factory transport protection film which is almost invisible glued to the lens of the camera. This protective film is so well adhered that you realize only after some time that it is present at all.
On the one hand one can notice the fact that this scratched very quickly and thus looks ugly, or on the other hand, that a matter accumulates dust. Especially if you carry the Samsung Galaxy S4 in your pocket, you see after some time, in the recess in the center that collects dust there.
We have changed somewhat the contrast to make the dust more visible.
This is also the reason why we recommend to remove the protective film, because the dust combines with the adhesive substance of the protective film and is very difficult to clean after some time from the lens.
On the other hand, this dust, if it occurs in larger dimensions, as in our image a slight impairment of the pictures taken.
The protective film, which is glued only for reasons of transport from Samsung on the lens of the camera can be relatively easily solved with the described by us trick of the Samsung Galaxy S4.