Dust Spot
Sometimes there is dust on the digital camera sensor. It's difficult to see on the image (sometimes) but our screener have to check for this problem and have to reject such images. Below you see two images (both are the same). On the first image you'll see the dust on the upper right corner (look twice!) than see the other image (contrast very high, changes with the imageeditor). You can now clearly see the dust spots on the image. In such cases you should contact your camera dealer to clean your sensor.
see the dust-spot in the upper right corner
now you clearly see the dust spots
