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How often should I get my CCD/Sensor filter cleaned?
If you have intrusive dots on your images and it’s annoying or it’s an effort to Photoshop out the dots – it’s time to get the filter cleaned.
Most dots will show up in a low contrast image.
To test the camera for dust take a picture of a white wall or a blue sky. If there is dust on the filer it will show up with less contrast images and a small aperture
Small aperture - stop down the lens to the highest number on the aperture ring ie: F22.