The Amateur Photographer is reporting that Pentax has released a statement confirming that some Pentax K-5 DSLRs were shipped with a defective sensor. It is believed by Pentax that this problem was a manufacturing issue and that the problem has been corrected. The statement from Pentax reads:
We would like to express our heartfelt appreciation for your patronage of PENTAX products.
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.
All users of these defective products will receive free repair at our service center.
We sincerely apologize 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.
On a bit of a personal note, I bought a K-5 DSLR and it had this “sensor stain” problem. I returned my defective camera to Pentax USA (repair center) and it was promptly replaced with a brand new camera. Kudos for Pentax’s high level of customer service.