Dirty Sensor – How Do You Know?


A portion of a photo severely marred by dust on the camera's sensor.
These dark spots the sky is caused by dust on the camera sensor This, by far, is the worst I’ve ever seen. But I successfully cleaned it!

Dust on your sensor. You’ve heard of it. But how do you know you have a problem? You’ll see it!

An example, from one of my own cameras. Here’s my buddy, aviation photographer Arnold Greenwell, hamming it up with the dire “No Photography” sign at the entrance to the Air Power over Hampton Roads airshow at Langley Air Force Base in Hampton, Virginia. (This rule is waived for a public air show.)

I had neglected to check my camera after the previous day’s shooting, and was dismayed to find that an entire day’s, and much of the previous day’s shooting at this once every few year event was ruined. All images had black blobs. It’s possible to clean up a few dust spots. But each photo had hundreds, or thousands. Damaging several hundred images. Cleaning a dust spot in Photoshop or another editor doesn’t recover the image lost under it. It’s a process of covering up the spot with an approximation of what you think it might have looked like, hundreds of times over. Doable on a sky. Tragic where there’s detail, such as on a face. Hundreds of spots, hundreds of images. I preferred to consider the day a waste. It broke my heart. I needed to clean my sensor.

These spots are shadows of dust on the front of the sensor. Actually, on a thin sheet of glass in front of the sensor. Each dust particle prevented light from the image from reaching the sensor. Not as obvious with a wide aperture. But glaringly obvious when approaching f/22, as I did here. At smaller apertures, the dust shadow is more focused. thus more obvious. Check your sensor for yourself. Stop down to f/22 or even f/32, and shoot a blank sky. Examine the photo carefully. You WILL find blobs. Those blobs are shadows of dust, or sand, or pet hair, or salt spray on the front of your sensor assembly.

Every interchangable lens camera, by their nature, gets spots on their sensor. Even if you don’t ever change lenses. As a lens is focused or zoomed, elements move. That stirs up air inside your camera, and with it, dust. When a sensor is energized to record a photo, it’s got a static charge. And that attracts dust to the sensor.

Cleaning a camera sensor is routine maintenance., much like changing the oil in your car. Having your sensor cleaned gives you a fresh start. It’s far easier to have the sensor cleaned than to correct the same spots over and over on many many images.

Need help? I can help! Via my OBX Sensor Cleaning service, I offer very affordable walk-in sensor cleaning clinics. Or I can come to you in the Outer Banks area by appointment. Click OBXSensorCleaning.com for more info and the current schedule. Visit my next clinic, or make an appointment today!

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