Why does my Canon 550D make a small sound while focusing?

Question

Ok the "noise" I am talking about here is not noise in photos, it's actual small noise/sound coming from camera.

I have been using my camera for around 6 months, but never noticed this before. May be because I have been with people/outside. Last week I was sitting alone at home, and focusing on an object when I noticed small noise from sensor. The noise comes only when I half press the shutter button to auto focus, and stops as soon as I take off my fingers from button. The noise is like a computer fan..but not that loud of course. Should I assume this to be normal?

Asked by vishal.biyani

Answer

The only sound that would come from the sensor itself would be a self-cleaning function, which only happens when you run the self cleaning, or turn the camera on/off. The sensor vibrates to shake off dust. This would not be happening when you are shooting.

When you half press, the sounds you might hear would be from the lens AF motor or image stabilisation (IS). Try putting the lens in manual focus and turn off IS if your lens has it, and see if you still hear a sound.

Answered by MikeW

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