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Russell A.
Russell A., Camera and Video Technician
Category: Camera and Video
Satisfied Customers: 6026
Experience:  30 years of experience as a TV station technician gives me a unique understanding of technical equipment issues.
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I have a Nikon D300 that I haven't used in over a year. My

Customer Question

I have a Nikon D300 that I haven't used in over a year. My Nikon D600 is in the repair shop so I took out the D300 and after 1 shot I now have an Err message and am unable to see anything through the viewfinder. The shutter works but the image is black. I cleaned the lens contacts with alcohol and removed the battery and memory card for 15 minutes, as recommended by an online site, but the problem persists. I see that the mirror is locked, so I did the procedure of locking the mirror for cleaning and then shut off the camera to unlock it, but it not work. Do you have any recommendations?
Dianna Ricky
Submitted: 1 year ago.
Category: Camera and Video
Expert:  Russell A. replied 1 year ago.


Unfortunately, there is no camera function that will reset the mirror if it is stuck due to either the spring or other secondary component corroding bring out of alignment . The long idle time, depending on how the camera was stored may have damaged the mirror mechanism. Gently, touching it only on the edge, try to move the mirror. Do this in a clean area with hands as dust free as possible. You can also use a wooden or plastic toothpick so that your hands do not touch the glass. If the mirror cannot be freed up to lift and return properly, the camera will require professional service to repair the sub-mirror assembly.

Please keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well.

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