[jrforman]

I bought my K-5 in Tokyo in MAPCAMERA and paid no tax and got international warranty with no additional price. After paying in store I check the body with my own lens and saw the stains.. With no question asked got a new one. BTW - at the store I logged in to this forum to show them the stain problem.

2. After using the camera for few x00 pictures an LV - I noticed the string of pearls at the upper center of the sensor and it's visible on the sensor too. Have a ref pictures at F22 and F45 from the purchase date and it wasn't there. It is possible ???

Yep. Got my camera in mid October and stains didn't show up until mid December.

[ml320x5]

Same here. No stains when new but after a month or so usage, the bloody stains showed up. I am concerning the new stock may have the same problem.

[dcmsox2004]

?? how is it that the stains are appearing later in the life cycle of some k-5 bodies, when initial inspection at say f22, reveals none??
this is mystifying and most unsettling as i was going to purchase a k-5 very soon, until i started reading these posts.......
moreover, has our friends at pentax/hoya been contacted to address this specific issue ????
it's one thing to have a body with sensor stains when first inspected, it's another problem entirely if the stains appear after useage...........
this can't be rocket science to pentax, can it???????!!!!!!!!!!!

[bobmaxja]

Seem the new production, problem is resolved. The one that are finding stain later are from the early batch .

[Cannikin]

?? how is it that the stains are appearing later in the life cycle of some k-5 bodies, when initial inspection at say f22, reveals none??
this is mystifying and most unsettling as i was going to purchase a k-5 very soon, until i started reading these posts.......
moreover, has our friends at pentax/hoya been contacted to address this specific issue ????
it's one thing to have a body with sensor stains when first inspected, it's another problem entirely if the stains appear after useage...........
this can't be rocket science to pentax, can it???????!!!!!!!!!!!

Apparently the stains are from some residue left somewhere in the sensor assembly. The sensor heating up causes the residue to evaporate and then condense on the glass. Thus, the stains will often not appear until after some use.

[peterh337]

Does the sensor get warm?

If evaporation is happening then the proper test will be to leave the camera doing interval shooting for the max 999 images, 1 per second.

I wonder if Australians get more stains? A higher ambient would help.

[Cannikin]

Does the sensor get warm?

If evaporation is happening then the proper test will be to leave the camera doing interval shooting for the max 999 images, 1 per second.

I wonder if Australians get more stains? A higher ambient would help.

Yes the sensor heats up considerably with use. The biggest heat generators by far are video and live view, to the point that it can overheat and shut down.

The stains on my camera showed up after using video for awhile.

[garyk]

Thanks for the info Ofer hadas
I will keep an eye on mine.

This is just a shame for Pentax. Finally, a really good camera. And this happens. They just cannot win.

[peterh337]

I've done several 8 minute videos (all one can fit onto a 16GB SD card) and no evidence of spots.

If somebody really wants to test this, they would need to warm the camera to its max rated ambient, use it a lot, and then leave it to cool in the least favourable orientation.

I might try warming it up a bit next time.

This is a bit worrying because it is fairly obvious that such a defect could remain undiscovered for a very long time. The only time the sensor might get hot is during production soldering and similar operations.

I have an electronic manufacturing business and have had 1 or 2 such "events" over the years... fortunately I managed to recall all affected products by S/N, very quickly, having sent out replacements by DHL beforehand.

[Nomad]

Apparently the stains are from some residue left somewhere in the sensor assembly. The sensor heating up causes the residue to evaporate and then condense on the glass. Thus, the stains will often not appear until after some use.

Done!!

Received my K-5 today and it had stains on the sensor. I am going to get my money back and settle for the k-x.

I cannot (will not) spend $1500 on a camera just to worry that stains will show up at a later date.

If my wife and I didn't have enough lenses to be committed to Pentax I would be jumping ship to either Cannon or Nikon....there is just no excuse for not putting out a technical bulletin to their distributors detailing how to inspect for this issue before sending cameras out to customers.

I am just steamed

[bobmaxja]

Where have you bought it? What the serial #?

[Nomad]

Where have you bought it? What the serial #?

started with 386 (I think) and bought it from Abes of Maine. They took the camera back without any problem with a UPS label on their dime so I don't have a real beef with them but right now they are panning on shipping me a replacement but I am not going to chance it. Just going to get my $$ back....I am actually very sad as I was so excited for this purchase

[bobmaxja]

Knowing the serial # that was risky. Pentax have published info to their dealer. Abes decided to ship anyway. Not the fault of Pentax

[goldenarrow]

Can anyone repeat the info about what serial # series starts the "defect-free" sensors? Is there a clear (identifiable) demarcation between susceptible/suspect sensors and the date the problem was fixed? Somewhere it was said December 18th, 2010 was the date of manufacture for the production fix. What serial # starts on that date?

How do they KNOW that they fixed it? A substance in sensor assembly sounds like they found what they thought was the cause. Is it substantiated that their theory has born-out to be true?

Sorry if I am repeating similar questions from a month or two ago, but I don't have time to read 18 pages of this thread! Thanks for any specific info.

[goldenarrow]

An extra thought: Was/Is the defect from sensors/AA filters gotten from Sony? Or is Pentax admitting that their own assembly procedure was flawed? Is anything about the CAUSE truly verified about this situation?

WHY should I buy this camera a year or so from now if the root cause was never owned by anyone and fixed? Is Nikon having the same problem since they get the same sensors from Sony???