K10D Spot on some images. Help Please.

Help Please.

I shot around 100 images today and during processing noticed a pretty large spot almost in the center of some images.
Was shooting for our Fire Dep't in temp of around 28-30F for about 2 hours using various apertures, which I know can affect how much a dust spot shows up, or maybe not at all.

I haven't had any problems prior to today. Changed lenses last week and shot event just fine, then changed back to another lens just prior to today's event.

I have tried a bulb blower. In camera dust removal about a dozen times. Camera Sensor clean feature three times, all to no avail. Also tried another lens and the spot is still there.

Anyone have any ideas ? Only had K10D for 6 months.

Thanks, RG.

PS.

Have owned another DSLR without dust removal feature for over 3 years, changed lenses many times, never a problem with spots on images.

Using a small aperture, if you take an image of a blank wall or even blue sky then any dust spots will show up.

The SR system can be used, several times probably, followed by rocket blower and finally as a last resort by physical cleaning.

I would use the Pentax kit (no surprise there0 but if you use others be aware that the K10D sensor has a special coating that may potentially be damaged if the wrong liquid is used. I have no idea which is the right liquid...

There are bulb blowers, and bulb blowers. The wussy ones are probably no use at all, and even with the rocket blower that I use, I find I have to get the nozzle right in there - so it's fully charged battery, mirror up, and a careful braced holding position, so that nothing moves except the dust when I give the thing a good hard squeeze.

There was a K10 listed on E-Bay last week which stated it had a spot in the middle of its images. The seller said it was a scratch on the sensor so be careful if you are going to be digging around in there

Does anyone know if a scratched sensor is repairable, is the coating over the sensor replacable :

Yes, absolutely. I guess I get the nozzle to within about 1cm of the sensor, so a bit further in than the mirror. That's about as close as I dare go, and I haven't needed to go any closer.

I can't imagine it could be done more cheaply than replacing it.

One time when I was using my Rocket Blower on my *istD I got a bit carried away and bashed the nozzle against the sensor. Twice.

It suffered no damage whatsoever.

I wouldn't recommend doing it, but I suspect sensors are a little more sturdy than popularly believed. Haven't tried it with my K10D though.

But the Rocket Blower has done the trick so far with any dirt that's appeared, like Matt I haven't had the need to resort to touching the sensor with anything (used to do it every couple of weeks with the *istD, sensor swabs and Eclipse fluid).

Dan

If you are going to use Eclipse fluid on a K10D make sure it is E2 fluid, not standard Eclipse fluid!

I've not yet had to resort to a liquid cleaner for my Ist Ds. The Arctic Butterfly does the trick for me. Not that I need to clean it all that often.

Hotshots - maybe if you posted a couple of photos folks here could offer mor advice?

Thanks to everyone for all the suggestions.

Gwyn.

As requested, here are a couple of samples.

It was a very dull overcast misty very cold morning and of course lots of smoke for the training session.



Right by the hand.



In lower area of smoke.

Thank you, RG.

It's in a consistent position and looks like some debris on the sensor.

a peice of debris that big should be visible if you remove the lens and lockup the mirror ....

John,

Thanks.

I locked the mirror up once again, held the camera under a bright lamp and gave it three good blasts with a Rocket Blower right above the sensor. You would not believe the big chunk of debris that flew out of there. Certainly big enough to see in the palm of ones hand (If I could have found it)

How on earth could something that big get in there is beyond me. I am very careful changing lenses, I never ever put a lens on without using my blower first and have not had the problem with my other over 3 year old DSLR.

I am beginning to wonder if it was floating around in the body from new.

Anyway thanks to all for the help.

Cheers, RG.

Or in the blower, if you use it every time you change lenses. Maybe the plastic is breaking up inside. Or maybe it's a chunk of grit from all the burning.

Doing it that often is excessive, IMHO, though. There's no point taking the risk of blowing something on to the sensor as often as every lens change.

Just do it when you notice a bit of crap on there, and clone it out of the images it affects.

ChrisA.

The blower I am using is only two weeks old.

I just use the same procedure I have always used for years, starting with SLR's and my other over 3 year old DSLR.

You could be correct in overkill, but it's mostly the end of the lens I use the blower on, don't see where that could cause a problem in the camera.

Never have changed lenses on a Fire Dep't shoot, I either take the Pentax fitted with the new 18-250. Or I take two camera's with different lenses fitted.

RG.

I suppose an almost new one might have loose bits too. I don't know - I'm only speculating. You were probably just unlucky.
Ah well, sure, but you didn't say that. We were all talking in the context of shifting muck from the sensor. Sure - a blast at the end of the lens is probably no bad thing just in case it's picked something up.

You'll probably never know what caused it, so no point worrying.

my first ever camera was a CPS Olympus AAAAAAges ago. It had a zoom lens and the same thing happened. It had to go away to be dismantled and cleaned. The whole thing wasn't cheap. This why i love the K20D. It does all of that for free and instantly.