Those annoying specs on your digital camera come from sensor dust. And there are lots of things you can do to help reduce or eliminate that dust.
If you own a digital single lens reflex (DSLR) camera, the kind with interchangeable lenses, sooner or later, you will have to face the fact that dust will start to show up as specs in your images. You should take action to remove this dust on a regular basis.
Here are some quick tips to help you control that dust.
1) Make sure you turn your camera off when you change lenses. The static electricity that surges around your camera when it’s powered on attracts dust.
2) Make sure you always have a lens or a body cap on your camera.
3) Exercise more care when changing lenses in a dusty or dirty environment.
4) Avoid push/pull zooms since they actually pull air INTO the camera body bringing dust along with it.
5) Clean the backs of your lenses and even your body caps once a month to make sure they are debris free.
6) Get a large blower bulb and regularly blow out the dust from your camera body. DO NOT USE CANNED AIR!
7) Use a sensor swab when the sensor is really dirty and blowing air won’t help.
Depending on your situation, there are many sensor cleaning alternatives. I use a combination of a LensPen and the Visible Dust Sensor Swabs to take care of my Nikon D3.