Sensor cleaning... not

No (face up) and Yes (its off), respectively - I need to see where the orange dots are to line them up; try to spend as little time as possible with exposed sensor. I've seen other people change DSLR lenses and never noticed them trying to do it upside down...

Also put the rear lens cap that I took off the new lens on the old lens pronto (and check the new one for dust/fingerprints before starting, just to be sure).

I'm an eczema sufferer (probably "eczema victim" as of this century) and produce lots and lots of "DNA evidence", sorry dead skin, which I shed over every "(potential) crime scene", sorry place I visit. So the dandruff thing is not said lightly as one will probably be leaning over the lens looking to line up the orange dot.

Surely the silent AF is down to the lens and can you not use the select focus points on the KX you can on the K20 and the K7. As I do not own a KX I can't really comment but it does seem you are blaming the camera body for somthing that may well be nothing to do with it.

ho ho although with me, it would be suspicious long hairs getting inside it (they seem to get left behind everywhere else I've been). No dandruff/eczema issues thankfully.

I could try hoovering the bags out, but the main bag is a LowePro that opens up sideways and top so dust would fall-out instead of accumlating.

Loose macaroon? No, but if you've got a doughnut handy. Mmmmm... Doughnuts....

Yes the silent AF is down to the lens. However, I don't own any SDM pentax lenses, so can't say how they compare (although everyone moans they are slow) - anyway with the horror stories about Pentax's SDM failures... no thanks, my bargepole isn't long enough!

Kx has focus points you can select...on the rear LCD, rather slowly. There's isn't even a centre target circle is in the Kx viewfinder (even the old film cameras I used 20 years ago had these...). Frankly, its hopeless as a composition tool - either go for Centre or Matrix, either way you have to pray a lot...

On the D90, hold it up to eye, it showed the various points and then highlights the ones its focusing on, move slightly and semi-press button again, it picked some alternative points - was almost psychic in its abilities to guess what I was interested in (random looking out of window at garden, plenty of opportunities to pick the "wrong" things but it was damn good). I've not used a K7 or K20 so don't know if it has a similar system or not, but the speed was way in excess of anything I've seen from Pentax. And silent. No whirr whirr whirr...

I'd practice trying to change face down, flossie. This could make quite a difference. I don't find it too difficult - though always change lenses on as flat a surface as possible with the new lens aligned as well as possible.

You can easily select focus points on the K20D, though it doesn't highlight the focus points in normal use as thoroughly as Nikon (or Canon).

I leave the sensor cleaner on all the time.
I always change lenses indoors and make do with the one I fit for the rest of the day (!)
I change lenses with the K100 upside down.
"Prepare" the new lens by vigorously blasting the mount and rear optic with a blower brush then switch lenses as quickly as possible.
I use the blower on the "old" lens before fitting the end cap.

And I still get specks on the sensor!

As John says though, if you've every tried "spotting" prints made with dusty negatives, the odd mark which can be cloned out on a computer is not a huge problem.

I can't help but take this sort of statement as a challenge, and I go and look at some photos... Actually, most of yours seem pretty clean, but that may be because of your liking for wide apertures. A couple of your pier shots show a black dot on the left hand side, but the 'Private Property' shot on the Red Bubble site is littered with dust-spots, although don't know when you took that one.

I meet many people who claim their sensors are clean, and that they never need cleaning. I haven't seen one yet that didn't prove them wrong.

Dan

Take one photo with your shortest focal length at the highest f-number and please show it too us

The dust increasing as the day goes on is bizarre. That would imply daily cleaning of a sensor and that can't be right.

I have no idea if this is possible, but could the sensor somehow have gained a charge that is permanent? Could it be permanently switched on even when the camera is off?

Otherwise, does a lens have something inside it that is fragmenting and scattering dust? Perhaps some rouge manufacturing debris?

I think it needs looking at by a professional repair house.

Ah that's it - I'm being stalked by someone from the Make-Up dept


Anyway, I'm holding judgement until SRS get the Butterfly to me (out of stock), then there will be some very systematic testing and probably far more F22 photographs of the sky than is healthy...

p.s.
I've shot somewhere over 3,000 frames on the Kx in under 4 months. By entry-level DSLR standards - or even mid-level - its been subjected to waaaaay more than normal usage and environments, let alone lens changes!

You couldn't make it up....

I reckon the dust is coming from the cheap brake pads that your garage palmed you off with.

G

Thought it might have been, it had a look that was very familiar...

My *istD needed a wet clean every couple of weeks if not more. My K10D has only ever needed a rocket blower every now and again, it's much better at shrugging off the dirt than the D was.

Dan