How do I know if I need to have my sensor cleaned? Take your camera outside on a clear-skied day. Set your camera in "continuous" mode. Point the camera at some blue sky, and shoot about 10 pictures moving your hand slowly. Review your pictures, and scroll through them at a semi-fast pace. Notice any dots staying in place while the camera moved? That would be large dust particles. You will be able to see more dust if you vire the pictures on a computer. Oh shit, I have dust, what do I do? You should probably get it cleaned. The easiest, quickest way to remove 95% of dust is an air blower. (Like this) For tougher dust, you may need to use something to physically push the dust off the sensor. I reccomend PhotoSol products (www.photosol.com) I have an air blower, what do I do now? Remove your lens. Go into your camera's menu and find the "mirror lock up" or "sensor clean" option. Hit it. (Note: Don't fuck around with this option if you aren't actually gonna clean the sensor.) The mirror will pop up, and stay up. Behold the almighty sensor. Keeping the sensor facing towards the ground, hold the Rocket Air at a 45 or so degree to the sensor, and pump away. Move it around, and spray air from different positions. Don't touch the sensor. I still have dust after using the air blower! Purchase a product made to clean sensors. Read reviews about it. Read the product's the directions, and be very careful. I reccomend Photographic Solutions' Sensor Swabs. I've used them personally to clean all kind of sensors, and I find I get the best results with them. However, other products are available. How you should never clean your sensor. NEVER use canned air. Canned air sprays oils, and can actually adhere the dust to your sensor. NEVER use a brush. A brush can scratch your delicate sensor. TRY NOT TO use compressed air. Compressed air can propel a small piece of sand, or the likes into the sensor. Essentially sandblasting it. Figured I'd type that up. Anyone have anything else to add? Sticky?