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Russell H.
Russell H., Service Tech
Category: Camera and Video
Satisfied Customers: 9309
Experience:  8+ years of professional experience
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I have a Nikon D40x camera with an AF-S Nikkor 18-135mm lens.

Customer Question

I have a Nikon D40x camera with an AF-S Nikkor 18-135mm lens. The Auto-Focus is not working. when I try to focus on a subject it moves in and out 3 or 4 times and when it stops the image is blurred. So I have to use manual focus. I don't know if the problem is with the lens or the camera body, or a setting is set wrong.
Submitted: 6 months ago.
Category: Camera and Video
Expert:  Russell H. replied 6 months ago.
Hi, thank you for contacting My name is Russell. I will do my best to provide the right answer to your question. The problem may be with the lens or the camera - but I would guess it is more likely to be with the camera body.(To be certain, switch the lens with another one. If the defect continues, it is indeed the camera body.) If manual lens focusing still works, the lens optics at least are not defective, I think. As for whether it is a setting... can you tell whether the way Auto-Focus stops is focusing too close (so that the camera has to be moved toward the subject) or too distant (so the camera has to be moved away from the subject) ? try moving the camera, and see. Go through your camera's Settings, and see if there is a feature calledAF Fine Tuneamong them. If so, your camera has AutoFocus calibration, and can be adjusted without being sent back to the manufacturer (though admittedly a group of Nikon D800 cameras recently turned out to have an autofocus issue that could not be recalibrated and required return to the factory. Let me know, and I will advise you further. (If your camera does not have AF Fine Tune, then it probably will have to be sent to Nikon for repair, with a note that the autofocusing stops (either too near the camera, or too far from the camera.)