Dust?

I noticed a few marks on some of my images but only some of them.

After a bit of head scratching I discovered that they only appeared on those taken at slower (couple of seconds or more) shutter speeds.

After giving the lens a good old clean it improved but there was a funny blob that wouldn't go away.

Turned out to me some stuff on the sensor.

Found a good way of checking for 'stuff'.

Take a picture of a white piece of paper or a pale wall at a quick shutter speed = clean result.

Change the shutter speed 20 seconds for example and take the picture again = the blob appeared.

I had that problem once, then I cleaned my glasses and the marks dissapeared

Did you clean the sensor afterwards? How did you do it?

We have sensor cleaning equipment but not had to use it yet (fingers crossed)

The 400D automatically cleans the sensor each time its switched off. personally, i wouldnt mess about with the sensor, id send it away if it needed to be done.

Just mirror locked it and gave it a gentle blow - thankfully nothing was stuck to it.

There's a few products that can be used but it's best avoided if possible.

Dont just wipe it though.

Only a dust remover Dawn Anything else (ie something heavier) won't be removed as far as I know

This timing of this thread is incredibly apt since I cleaned my sensor for the first time this morning

For the last 18 months, I have had visible dust on my sensor however it is largely unnoticable until I start using apertures of f11 + so I have ignored it. I had decided to send my camera away to have the sensor cleaned however I did a test shot this morning (shot at a cream wall using an Aperture of f32) and the dust was worse than ever. After a lot of deliberation I decided to have a go at cleaning the sensor myself. I have a sensor cleaner that you dab on to the sensor and it lifts the dust off.

I must say I was very pleased with the results. I wouldn't normally have bothered except for the fact I wanted to go to a particular place to shoot this morning (though as it turned out it was closed due to the F&M restrictions, we are in the Surveillance Zone this time - just outside it last time and the place I wanted to go was completely closed off ).

I had this exact same problem with my last camera. generally a rocket air blower will get rid of most of it, once a sensor gets dirts it is the devils own job to get it clean, I didn't have sensor cleaning kit at the time . the only other solution is to send the camera away for cleaning.

Bazza

This is a major factor why we are thinking of getting a top end compact to a DSLR how much of a problem is this...It seems to be a thing that is causing my husband a lot of concern...
Sue