New Sensor?

As Mannesty says, you CANNOT touch the sensor.Its behind glass. Getting back to the OP, I dont think a soft plastic blower brush will have scratched the glass, more likely it has left some greasy residue.

If it's called a lenspen, it implies it's designed for cleaning lenses, so don't assume it's OK for sensors.

We know the actual sensor is covered by a filter, but the filter is fragile too. There are specialised products for sensor cleaning, so when necessary use those. When necessary.

So far from the *istDS to the K10D and now the K20D I have not so far found the need to use any sensor cleaner that makes contact.

When i think of all the dust that used to mar negatives and all the spotting big prints needed, I think we might be getting over anxious about our relatively dust free sensors. After all, it's incredibly easy to do a bit of spotting in Photoshop!

You CAN clean the sensor and it CAN be touched in the process (with the right gear) that is of course to say the glass filter can be cleaned Johns advice is good though dont clean it unless you have to. these links may be useful in dispensing with your fears.

link

link

And there are many more on the market

You can also try a search on youtube for "sensor cleaning" videos

Here is the mark in all its glory, it only starts to show up around f16.
This was at f32.

Which one?!?

There are a load of spots and lines on there, I think it's just time you did a wet clean if they're not coming off with the blower brush.

I bashed the sensor on my *istD with the tip of my rocket blower, didn't do that any harm. Although I wouldn't advise doing it (bashing the sensor, I mean), I think the majority of the warnings (from the manufacturers) about not touching your sensor is in order to encourage you to send your camera off for cleaning (to the manufacturers).

I wet cleaned my *istD every other week, because spots were always showing up on that. The K10D's much better in that respect, but I'd still much rather clean the sensor than have to go through every photo with the healing brush.

Dan

I can see 5 sensor blemishes and if its the one about 2thirds down on the right hand side, then I would call that a significant mark, but I also think its something on the sensor rather than being a scratch.

Actually the marks down the bottom are where I (badly) cloned out a ruddy great lampost, its the one to the right I am concerned about.

Sorry Mike, my monitor didn't show the whole picture in the forum, clicking on it brought up the complete image so I now see that it's bigger and darker than the other marks.

Have a really close look at the sensor again, use a magnifying glass (or a reversed 50mm lens) and check the top left hand corner of your sensor, as that's where this object/scratch is. I would expect you to be able to see it.

Dan

Ok, finally spotted it, I am 99% certain it is a scratch now .. it reflects back if you catch the sensor in certain light and I gave it a good rub with my sensor cleaning pen which didn't make any difference whatsoever.
It's not often I shoot near f16 so I can live with it until I return back to the UK.

I think .....

Hells bells, That rocket blower must have a diamond tip on it

I would look at getting the glass filter covering the sensor replaced. I'm not sure what that would cost but it should be significantly cheaper than replacing a sensor. ::

It more than likely would be.
I will get it off to Pentax when I return, I like the idea of them returning the camera at no cost to me if I dont like the quote they give for the job.

This looks exactly like the smudge I had on my K100D a while ago. Cleaned the sensor using Sensor Swabs and Eclipse cleaning fluid. Worked very well!

Just make sure you get the right fluid. Eclipse for K100D, E2 fluid for the K10D (because of different sensor types).

Have you seen this site about cleaning? It was linked from the Micro-Tools site in the thread about lens spanners.

shim

The LensPen company makes a version of their product for cleaning sensors: SensorKlear. It is the same as the their lens cleaning pen except it has a square soft felt tip instead of a round one to access the edges and corners.

Not even Pentax say you that should never touch the sensor filter with anything because there is a Pentax cleaning product that does touch the sensor - a bit of jelly on a stick.

The SensorKlear does not always remove non-permanent stubborn marks though.

That is what I have used on the sensor but it's def a scratch, you can just tell by looking at it in certain light .. a bit like a scratch on a cd or piece of glass.

Pentax can sort it I'm sure.