Secondly, hold the camera facing down to minimise particles in the air from entering – see photo right.
And fourth, before you attach the new lens, ensure its rear surface is also free from dust.
Once again hold the camera body facing down and remove the lens. Then select the option in your camera menu to clean the sensor. This simply flips open the mirror and opens the shutter, revealing the sensor filter’s surface; most cameras demand you do this with a fully-charged battery or even a mains adapter to prevent the mirror from flipping down unexpectedly.