Pentax are advising users of about a batch of K-5 DSLRs released with a stained image sensor.

The Pentax Imaging website says: "We deeply regret that the first shipment of our Pentax K-5 digital SLR camera included some products with a stained image sensor — a problem which we believe was caused during manufacturing — causing them to occasionally produce images with spots which look something like water drops, and which users cannot remove with ordinary cleaning methods. We sincerely apologise for any trouble and inconvenience this problem may have caused. We also promise to do all we can to achieve the highest level of quality control in the future, and eliminate any worries our customers might have about our products. We sincerely appreciate your kind understanding and cooperation regarding this issue."

If you are a K-5 owner and have one of the faulty sensors you can get your camera repaired for free at a Pentax service centre.

We suggest you contact the retailer you bought your camera from for more information or visit http://support.pentaximaging.com/node/1214