I would appreciate advice regarding a problem that recently started with my D90. On a recent overseas trip, day 9 of 11, the camera started malfunctioning. The viewfinder suddenly went dark like the lens was stopped down rather than wide open to allow framing and focusing. The same problem occurs with live view. The camera cannot achieve focus lock since the lens is stopped down. A Nikkor 16-85 lens had been mounted all day. When the lens is removed then reseated, the camera will take exactly one frame normally. I tried turning the camera off then back on without resolution. Replacing the battery with a fully charged one did not help. Resetting the camera to default settings did not help. The same performance with 2 other lenses was noted. Each and every time the camera will take one and only one frame normally, then the view darkens, with resolution for one frame only by reseating the lens. Cleaning the camera contacts has not helped. It definitely looks like a camera problem, such that after taking one frame, the camera does not tell the lens to open up. I would like advice about how to proceed. Should I consult a local repair shop to see if they can resolve the problem, or send the D90 to Nikon? Am I missing something?
#3. "RE: D90 dark focus" In response to Reply # 1 Thu 29-Mar-12 03:49 PM by OnTERRYo
Sorry to hear you are having problems with your D90.
I do not know but, to me, it sounds like a battery problem. Are you using after-market type battery(ies)? Always check the easy things first. Is it at all possible to check your camera with yet another borrowed battery? Maybe a fellow Nikonian or local camera club or camera shop. I bet wherever you bought the camera from would be willing to help. I suggest getting a third battery for trial only. If the camera behaves with the third battery, then it could be a battery issue.
Page 250 of the manual indicates that the viewfinder could be dark with an under charged battery.
Good luck with your problem.
"The Nikon did the work; I just happened to be behind it at the time." TP
Here are a few things to check that may or may not apply. Is the lens fully seated and locked in the mount? Could you be inadvertantly pressing the lens release button? Try cleaning the electrical contacts on the camera body and lens. Good Luck and Enjoy your Nikons!
Thanks for your replies. I again tried the camera with a freshly charged battery, but no resolution. The custom setting D10 is OFF The D90 will take one and only one frame with the lens aperature open, then the lens stops down making the viewfinder darkish but not black. The next exposure is very long due to the stopped down lens, but the camera lists the aperature as 3.5 but requiring a 1.5 sec or so exposure vs 1/25. Most of the time the light is too dim to achieve focus lock. Just loosening the lens then relocking restores normal function for only one frame.
I will always remember trying to get just one last picture of the Treasury in Petra that afternoon when the camera started to malfunction. Fortunately, my wife was using her Canon G12 and was willing to share for the next couple days. That shows the value of a second camera on a trip.
I expect to send the D90 to Nikon this weekend, and I will post results when they reply. Perhaps I will try cleaning the contacts one more time.
#6. "RE: D90 dark focus" In response to Reply # 0 Fri 30-Mar-12 07:20 PM by aolander
As previously mentioned, it sounds like the aperture stop down lever in the camera is bent/damaged and jams on the lens aperture tab. When you remove/change lenses or unlock and relock a lens into position, the aperture lever can move back into the correct position. It would then jam again afer an exposure is taken.
Alan, Thanks for your input. That makes sense. There was no trauma to the lens or camera, there had not been any recent lens change, but just a sudden malfunction. Hopefully that is not an expensive repair. My Nikon extended warranty expired last fall.
I sent my D90 to Nikon and it was received back today. The notation indicates that the aperture lever was repaired, and the technician adjusted autofocus operation, cleaned the CCD and did a general check & clean. The total cost was $225. The only hitch is that the body cap sent with the camera was not returned. I called Nikon about that problem and a message was to be sent to the service department.