this happens when pictures without a good watermark are uploaded. A good idea is to place a clever watermark over the whole picture so that the original object (ship) is not obstructed at all and no viewer is "offended" by that watermark. I think it should be possible that an automatism places a semi-transparent watermark over the picture, diagonal or horizontal once uploaded. This will prevent thieves. If one is interested in the original picture without a watermark, he can ask the photographer/copyright owner.
Yvon, Thank you!
[Admin note: this topic split off to give higher visibilityhttp://forum.shipspotting.com/index.php/topic,16599.0.html