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How the autofocus on my Nikon D100 DSLR? (Please read!)?
Ok, so I use to use auto focus all the time … when it worked. I've only turned off the manual when my camera would be a putter and not focus properly on the correct item. I do not remember when .. but suddenly would not auto focus more. When I switch it on automatically, simply continues to focus in and out and not on any object. My eyes are not as great as when I have so I can not say whether my pictures are blurry and such .. so I need help getting a new auto focus. I fell once, but before it is dropped, it was messed up still. Does anyone know how to fix this? Also, is there a way to get the dust and out as the inside a lens? Because every picture there is this small particle in the top center .. Is there any way to open a lens without breaking it? Thanks if someone can help. 
His habit AF CAMERA? Or your lens? Try putting a different lens on it and see if that self-focus. Do not even think about opening a lens. Do you know if the dust is in the lens of the camera body? It is best to take it to a camera shop for cleaning and maintenance.
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