sensor smudge on k-x

Got a bit of a problem. All my images (taken with a k-x) have a sensor smudge in the same place (tried changing lenses, and used dust removal facility). It tends only to be noticeable against a v uniform background, such as the sky.

Examples plus crops below. It is about 1/5 way down the frame and central. What can I do about it?

Try the sensor dust removal several times. Then a rocket blower. If still no success, then a cleaning kit may be needed. Others will follow with their recommendations. I've never had to use a cleaning kit, so can't help with that bit.

...any use to you? link

thanks both, useful info. Is there anything to be wary of when approaching the sensor?

Not really, be sensible and patient, i.e don't attack it with a screwdriver wrapped in a cloth , use proper fluid and brush and if necessary repeat the cleaning operation.

Do make sure the batteries fully charged otherwise the mirror may come down during the operation should the battery die on you.

If using fluid, dampen (not soak/saturate) a lint-free cloth Probably best to wrap it over the top of a cotton bud - the cotton should soak up any excess fluid), then gently wipe across the sensor, left-to-right, then up and down from the back of the sensor towards the front. If you can do this with the lens mount facing downwards, so much the better.. That way, any loose debris will fall out of the camera body.

Also, have a look at this YouTube video for further tips and advice...

link

Hurray! It has gone. Was a tiny speck, and my makeshift removal attempt was to direct a jet of nitrogen (from a gas preservation system for wine) at it, which seemed to do the trick. Thanks for the advice.

A jet of nitrogen

Pleased it worked for you but be extremely wary of using any pressurised gas/ air in the chamber. If a rocket blower is not powerful enough to blow it off - it needs wet removal or potentially anti static removal as it is stuck. Blasting debris off the sensor is not a good idea IMHO

Catl

I highly recommend the Arctic Butterfly, It spins a nylon brush with fine bristles which get a small static charge you then place it near, but not on, the sensor and any dust leaps off.

It's somethng you need to get used to with digital cameras and it not really a cause for concern. There are any number of ways you can clean dust off the sensor, including all those mentioned above. I would be very surprised if it doesn't happen again - don't be too worried about it as it is easy to clean off without damaging the sensor.

Regards
David

I think an ex-girlfriend of mine had one of those - but she never once used it for dust removal!!

If you used pressurised anything and got away with it then count yourself very fortunate. Usually what happens in the case of canned air is that moisture is blasted on to the sensor and evaporates very quickly.Not sure about nitrogen but still not recommended. It then becomes a huge and very delicate operation to remove.
I know you have been successful but there is only one method that I would ever recommend and it is this one,
http://www.copperhillimages.com/index.php?pr=tutorials

Many many sensors have dust with users totally unaware because they seldom shoot small apertures. The sensor has to be pretty contaminated to see dust at say f8,but at f13 it will show, at f22 it will be glaring.

I may be missing something here Donald, but the website you have provided a link to actually recommends a variety of methods including pressurised canned air! All of the methods described on the website have already been mentioned in this thread.

The truth is, as long as you use common sense, it is not difficult to clean your sensor and wet cleaning is the best method, assuming all loose particles have been blown off first.

The trick with wet cleaning is to use the correct lint free cloth and not to make it wet, only a little damp. It's easy to make a swab with a straight edge from a lollipop stick or chip fork, then wrap around this the lint free cloth and moisten with a drop of isopropyl alcohol. This has worked for me on the few times I've had to use it and even on a very dirty K-m sensor it has removed all traces of dirt without causing any damage at all.

Regards
David

Thanks, v useful advice