I borrowed a camera last week so that I could shoot some video. This is how dirty the sensor was:
That’s a shot of the blue sky, with nothing in it. The black bits are dust, hair and I don’t even want to imagine what else. To test to see if your camera is dirty, use a wide angle lens, or zoom out, set the camera to the smallest aperture (f22) or landscape mode and take a photograph of a clear sky with nothing in it. You may need to manually focus to do this. The little bits of dust show up as black spots. If you get faint rings, that’s water drops that have evaporated, or pollen drops that have dried. If you camera is this dirty it’s time to have it cleaned. We can do it for you, or take it to your local camera dealer and ask them where to take it. The average cost of a cleaning is about $50, and is worth it. These black bits will show up in your photographs and can be very bothersome when you’re getting photographs printed!