Little blob on my pics

Hi all, have only had the camera about six weeks, only taken 200 odd photos, always keep the lens on, and in my bag but i have noticed a blob on the top of each pic about a third in from the left. cant see any mark on the lens, so dont know what it is. My first slr so am afraid to fiddle about with it too much. any advice would be welcome. here are a couple of shots which show the problem.
http://www.flickr.com/photos/48140175@N07/5381165987/in/set-72157625891281138/
http://www.flickr.com/photos/48140175@N07/5382033124/in/photostream/

Dust on the sensor. Time to get a arctic butterfly, search the web you will find thousands of references.

Davex.

If your camera (you haven't said which it is) has the dust reduction function, turn it on. It may get rid of it. If not, get yourself an Arctic Butterfly, as davex suggests.

jeez, that was quick, went back to edit my pics and there was reply! I did read some older posts re dust etc. but my blob seems to change size but stays in the same place! Might not show up on the above photos but sometimes it is a little dark blob, but on others pics, it is larger and fainter...Will go hunt for a butterfly then.

Try a hurricane blower first. Less than a tenner. Sorted out my K-x with one.

thanks all, have k-x too. is there any end to the amount of gadgets out there? : Will have a look at the hurricane, the butterfly a bit rich for my blood.

Dust blobs will change apparent size depending on what aperture you took the photo at, so the mark will be largest (and faintest) when the lens is wide open, and get progressively smaller and darker as you stop down.

In fact when the lens is wide open you often can't see the blobs at all, but when you stop down a bit suddenly dozens of them appear

When you change lenses remember to first turn off the camera and then learn to remove and replace the lens with the body pointing down. It takes a bit of practice, but is worth doing.
It won't completely prevent dust bunnies but it will reduce their number.

Be very careful with a blower that you don't touch the "sensor". And again do it with the body facing down so the dust falls out, and doesn't just move to somewhere else in the body.

A blower will work on most dry dust, but may just move it to somewhere else inside the camera. If it gets into the pentaprism/pentamirror, it's more difficult to remove.

If it's pollen, it's sticky, and for that you need . . . . an Arctic Butterfly or a wet cleaning system which, if you are not confident yourself, is best left to somebody else to do it for you.

Seconded. Blowers are not so bad on lenses out in the open, but I would not use one in the body. The butterfly although not so cheap is a much safer option.

You could find a reputable camera shop who would do this for about £20. Or if you have a local camera club you might find someone who will do this for you. Or failing that get a ferry to the Glasgow or Whitby meets and someone will do it for you.

Thanks Greynolds, as an ex-pat Glaswegian, might be the excuse i need for a visit. will read camera manual tonight, think i read somewhere about dust removal tool? might have been daydreaming....

i will never use a blower again.....first time i used one it blew dust up into the pentaprism, although it was no longer on the sensor it was badly visible every time i looked through the viewfinder.

lucky enough i managed to blag currys and they gave me a new one

Since then though had it set to dust clean on start up and have not had a problem since

I must say my K7 sensor hasnt suffered with dust (Dust removal at start up is set) but I blew dust off the mirror. Now I have dust on pentaprism it annoyed me for a few days but I have got used to it now. And some of the worst specks seem to have moved off pentaprism with use since.