What are the black spots on my pictures ?

Well, if you happen to have a Digital SLR camera you ought to come across this problem once in a while. It’s one of the curses of having Digital SLR’s.
I recently had a wonderful road trip to Smoky Mountains in Tennessee, I was all excited to get the sunrise and the breathtaking mountain landscape pictures of Smoky mountains. So there I was early in the morning to get the early sunlight, I merrily took pictures of mountains and valleys only to discover that they has 3-4 evident dark spots on
Them. This really pissed me off as I am damn peculiar about sharpness and clarity of my pictures, and hate to retouch them using software. I might as well stay on the field and take few extra shots than to sit behind the computer screen retouching it.
The Problem: It appears that when I took pictures with greater f-stops generally f/22 the two dark spots were evident. At lower f-stops they were not that evident.
Cause: The culprit was dust. Before going to the road trip I had opened up the camera and cleaned the lens during that period the dust might have found its way into the camera body and on my CCD sensor. I freaked out and started looking on the internet to find something to clean the CCD sensor, as you might have guessed nothing cheaper showed up ! I found some instructions which described how to get rid of dust spots using a simple camera brush blower and that helped me, hope it helps you too.
What you need: A brush blower and a clean room.
Procedure: Latch your camera or put it in a cleaning mode ( you might want to refer to the camera manual to know how this is done )
Slowly remove the lens, you should be able to see the CCD sensor as the mirror is lifted up. Tilt the camera body downwards so that the dust does not settle down on the CCD sensor. Then slowly blow the air using the brush blower ( the brush can be detached from blower which makes it more effective). Make sure you do not touch the sensor. Try to cover as much area as you can. After cleaning put the lens back on the camera and take test shots to see whether it worked or not.
How to test ?
It’s simple to reproduce the annoying dust dots. Focus your lens on any plain white surface, try to make f-stop as larger as possible, I kept it f/22. Put everything out of focus so that it is easy to spot the dust particles. Shake the camera deliberately to get rid of any pattern. You should be able to spot the evil dust after you develop the picture.