Digital sensors if left exposed to the atmosphere are prone to attracting minute particles of dust resulting in imperfections that blot out parts of the image. Whilst they can be recovered in a computer, it is a time-wasting exercise.

For bridge and compact cameras with a permanent lens, because they are sealed, then dust reaching a sensor is not a problem. The moment a camera has a facility to remove a lens from its body such as a DSLR, then more care in camera design becomes crucial and one that should not be fudged.

A quality sensor with even a dedicated digital lens are not the only important features for a well-designed digital camera; if the sensor is not properly protected from dust, then these qualities are wasted.

The problem, or risk, occurs when changing a lens, exposing the delicate sensor to the elements. Holding the camera so that the lens faces the ground is not a satisfactory answer, especially on a wind-swept beach!

Protecting the sensor should be one of the first considerations in camera design, more easily achieved if it is designed from a blank sheet of paper. Personal research by the photographer will soon reveal which of the manufactures have tackled this problem diligently.