After months of complete frustration with the Nikon 24-70 mm lens on my D300 and after having sent both lens and D300 body back to Nikon for expensive repair only to be told they were within spec .. the problem was solved for free in 2 minutes. After lots of suggestions from the helpful folks here and ridicule from some others on Flickr, I finally determined the problem was with the D300 and not the lens. In desperation I called Nikon one last time before giving up and by pure luck, spoke with a nice person named DiAngelo. He said it sounded like a corrupted firmware problem and that I needed to delete all Custom Settings and start over. I said I did the "two green button" default restore before as suggested by other Nikon people and it didn't work. He said that wasn't enough.
The procedure was:
1. Hold down the two green buttons for 3 seconds.
2. Go into the Custom Settings menu (Pencil Icon) and click Reset Custom Settings.
3. Turn the camera off Remove the battery turn switch ON Hold down the shutter button for 20 seconds Turn switch OFF Replace the battery Turn Camera ON
I knew immediately that AF was working like it did when I first bought the D300. All a matter of staying with it and getting to the right guy .... Suddenly it all came into focus.
Wonder if something like this would work on a D200. I didn't realize that my D200 had two different, and outdated firmware on it when I bought it. I did update the firmware but still am not happy with the performance of the camera.
Photographic composition is the strongest way of seeing. ... Edward Weston "It is easy to take a photograph, but it is harder to make a masterpiece in photography than in any other art medium." Ansel Adams
>I didn't realize that my D200 had two different, and outdated firmware on it when I bought it. I did update the firmware >but still am not happy with the performance of the camera. Speculating on what your D200 focus issue might be the D200 has AF detection areas far larger than the viewfinder marks - illustrated on page 5 of the Nikonians D200 AF link - which leaves no stone unturned on D200 AF https://www.nikonians.org/nikon/d200_multi-cam_af/
Photography is a bit like archery. A technically better camera, lens or arrow may not hit the target as often as it could if the photographer or archer does not practice enough.
That third step of taking out the battery and holding down the shutter button is the same move advised for computers, to clear any residual charge in the hardware that may be holding onto corrupt software settings. I have been advised to to the same thing on my computer several times, to unplug, remove the battery, and hold down the on/off button for a full minute.