[Translation from Japanese to English ] Flash light can be reflected by dust and rubbish in the air and return toward...

Original text

空気中の埃や塵にフラッシュの光がそれらに反射して、カメラの方に戻って来ることがあります。
カメラにそれらが撮影されてしまうと、丸い白っぽい物体となって記録されます。
これは塵や埃のピンボケ画像です。

Translation / English

Flash light can be reflected by dust and rubbish in the air and return toward the camera.
When it's photographed it's recorded as round white-like entity.
This is defocused image of dust and rubbish.

Translation / English

When flashlight reflects dust in the air, the light may come back to the camera.
When they are caught in the camera, they are recorded as whitish round objects.
These are defocus images of the dust.