Nikon AF Nikkor 50mm f1.8 D focusing problems

etickarunan

New member
Hi!

I am currently using a Nikon d90 which has an autofocus motor on the actual camera body but when I attached this prime lens (name in title) it did not seem to auto focus. I can manually focus and take wonderful shots but naturally, auto focusing is preferred.
Any advice/comment would be wonderful.

Thank you :)
 

nickt

Senior Member
So nothing happens when you flip the camera lever to auto focus? Does the manual focus ring on the lens at least lock up? The focus ring on that lens should not spin at all when engaged with the camera for autofocus. Is the camera new to you? I'm wondering if it is and perhaps it is set up for back button focus and the shutter button is not doing the focus. Try pressing the ae/af lock button on the back to focus. To recap, check auto/manual lever and back button.
 

480sparky

Senior Member
......The focus ring on that lens should not spin at all when engaged with the camera for autofocus........

Incorrect. The only way to focus a 50/1.8 D lens is by turning the focus ring. Whether you or the body motor do it... the ring turns.
 
Last edited:

nickt

Senior Member
Incorrect. The only way to focus a 50/1.8 D lens is by turning the focus ring. Whether you or the body motor do it... the ring turns.
I see that I didn't say that well. What I meant to convey was that he should not be able to easily manually spin the focus ring in autofocus like you can on some other lenses. It would confirm right away that something is broke if he can manually turn the focus while the camera is flipped to auto focus.
 

480sparky

Senior Member
I see that I didn't say that well. What I meant to convey was that he should not be able to easily manually spin the focus ring in autofocus like you can on some other lenses. It would confirm right away that something is broke if he can manually turn the focus while the camera is flipped to auto focus.

You can also perform a visual check. Turn the focus ring, and watch the screw coupling on the lens mount. They should turn in harmony. You can also use a jeweler's screwdriver in the coupling to see if the focus ring turns.
 

etickarunan

New member
So nothing happens when you flip the camera lever to auto focus? Does the manual focus ring on the lens at least lock up? The focus ring on that lens should not spin at all when engaged with the camera for autofocus. Is the camera new to you? I'm wondering if it is and perhaps it is set up for back button focus and the shutter button is not doing the focus. Try pressing the ae/af lock button on the back to focus. To recap, check auto/manual lever and back button.

Thank you for the reply, but the ae/af lock button does nothing for this lens. The camera is not new to me but this lens is new to me. Also when the lever is on auto mode the lens focus does not lock up entirely but there is much more resistance compared to manual mode. When I try focus with the shutter button the lens moves ever ever so slightly but the image is always far from focused. I'm beginning to think it might be physical damage somewhere along the shipping process.
 

Woodyg3

Senior Member
Contributor
Not, not that button. The AF/M lever next to the lens mount.

nickt advised him to heck to see if the camera was set to back button focus. That's what he was responding to.

Can you check the lens on another camera? Do other lenses still work fine on your D90?
 

nickt

Senior Member
It sounds like something is wrong. Either the lens or the camera. Like woody said, maybe try the lens on another camera. Or if you have another AF lens (old style with no focus motor) to try. Maybe the camera drive is weak, but I have never experienced a bad camera or lens so I don't know how a failure usually plays out. Maybe try what sparky said with driving the lens with a small screwdriver. I just tried this on my 50, the screw turns very easily and the focus ring moves along with it. Be very careful if you try this.
 

etickarunan

New member
It sounds like something is wrong. Either the lens or the camera. Like woody said, maybe try the lens on another camera. Or if you have another AF lens (old style with no focus motor) to try. Maybe the camera drive is weak, but I have never experienced a bad camera or lens so I don't know how a failure usually plays out. Maybe try what sparky said with driving the lens with a small screwdriver. I just tried this on my 50, the screw turns very easily and the focus ring moves along with it. Be very careful if you try this.

I have one other lens which when attached to the d90 has no problems focusing correctly and quickly. Also with the prime lens, I found that when I try focus with the shutter button and provide a little turning aid to the lens with my hand, it manages to focus. This leads me to believe either the lens is a little tight or the camera motor is too weak for this lens in particular. Any solution to fix this?
Thank you guys for the fast responses, truly appreciated.
 

nickt

Senior Member
I have one other lens which when attached to the d90 has no problems focusing correctly and quickly.
But is that an AF lens? If it is an AF-S, the test doesn't show anything. The newer AF-S lenses have their own internal focus motor and do not use the camera drive. If you don't have another AF lens, my only suggestion is to try the small screwdriver to drive the lens as said above. It should be very easy to turn. If it is hard to spin or the effort changes at points, it is likely the lens. The 50mm is probably not worth having repaired, at least not by Nikon. The camera might be worth it. I don't know of any self-repairs.
 
Top