excessive noise

I have recently noticed that my images, even at 100 iso, appear to have more noise. Could this be due to the fact that I haven't cleaned my sensor in 1 and half years??? I have used the blower once or twice. I am one those who is a afraid of cleaning the sensor because of cost if I XXXX it up.

So could a dusty sensor = noise??

Any comments would be much appreciated.

Not sure whether you mean digital noise (and then, now you have more noise than what?), or do you mean sensor dirt. Post some example picture so we can find out.
If it is dirt, then it doesn't matter what ISO you use, and you shouldn't be too much afraid of cleaning sensor (or raher filter that sits in front of sensor), a bit of care and nothing bad should happen (you can find few guides what to do/avoid on the forum ).

A senor will always display some noise because but at iso100 the noise will only be really visible when viewing at or over 100% zoom and at the darker areas, this with CCD sensor a CMOS sensor I would expect to show more noise, certainly with the K-X because that's extended ISO.

There is a glass screen/filter infront of the sensor so the dirt/dust is on that and never on the sensor, so in a way you don't clean the sensor but the filter.

Thanks for the quick response. It is at 100% I see the noise and at 100 iso it is in the dark areas. Just one thing it seems more prevalent when I use my old lenses.

So infact even at iso 100 I should expect to apply some noise reduction especially if under exposed?


Thanks again

It depends on the image and the output size, if you've a lot of detail you hardly notice the noise but if you have a "flat" surface of one tone you see it quite well.

Here is a shot at iso100 unedited also with the K10D.
link
When you look at the part that's in focus you don't see any noise but when you look out the part that are out of focus you see the noise quite well.

Stefan, I think you need to clean your sensor

I think Terry is correct. If that link is a recent image I can see dust marks and your sensor needs a clean. Can you recommend a good kit.

Thanks again

Stefan

just clean it with a Arctic Butterfly the sensor has a filter over it so you Will not damage it
link

James

The Arctic Butterfly from Visible Dust is about the best dry cleaning system I have ever used.

Pentax themselves can supply a wet cleaning system, which you can buy from this site, but I try to avoid wet cleaning if possible. It takes practice to get it really clean and smudge free. I haven't needed to wet clean my K20D in almost 2 years of ownership.

Careless use of the rocket blower can cause more damage than either of the two methods I describe above. Touch the sensor with the blower nozzle and you'll be left with a permanent mark on the sensor and possibly dust behind the focussing screen which can be difficult to get rid of, though its not strictly necessary because it will not appear in images.

I know guys and that's an old shot and already cleaned it multiple times with an arctic butterfly