russault

It was bought from an individual on eBay, and I suspect that he bought it in Central America; the owner's manual was in Spanish, though the camera's data screens are all in English. It was just under $150, enough below market price that if I can get it fixed for under a hundred, I'm OK on overall cost. The seller has a good rep otherwise, and he appears to be someone who stepped up to the D300 from one of the mid-70s pre-AF bodies and stayed with his old collection of lenses. (Not gonna say this is a bad idea, because I don't know what or how he shoots, and apparently it worked for him well enough; the shutter count is over 50K.) I'm firmly in the DX camp, though, and the lack of automation is a no-go for me. Yes, from one standpoint, it would be "easier" to return the body and look for a different one, but if the bird in the hand can be taught to fly economically, I don't have to go though all the rigamarole and hassle of shipping and shopping. (Though at the moment, the local big used camera place has a D300 is semi-decent shape for about $225.)

Confirmed: No voltage across the connections for the lens anywhere, and at least two of them should have been at battery voltage with respect to at least one other with the camera switched on. There are several possible causes, but my electronics instincts still point me to the ribbon cable and/or the solder joints to the points on it just above the lens mount. We'll see what the tech says when I haul it over to the repair shop.

I found the repair manual online. The most obvious probable suspect is a bad solder joint to the lens contact ribbon cable, causing all of the powered lens functions to be down. But looking at the degree of disassembly required and the general "you really need to have done this before" nature of certain parts of it, I'm going to haul it to a trusted repair shop tomorrow.

The view through the finder is bright until the stop-down button is pushed, and then the results are as one would expect, so the body's lever for stop-down is working, but that says nothing about the lens' aperture servo, which appears not to be engaging. Also, I hear nothing from the VR widgetry - which is supposed to be quiet enough that I shouldn't, really. The AF results are the same whether I choose Continuous AF © or Single-Servo AF (S) on the selector next to the lens. Both lenses are in AF-capable switch positions on the lens itself. I have switched the positions multiple times, and the fact that they both work flawlessly on the D60 body seems to rule out a problem forward of the bayonet. I found out some more info from the seller; he had used this body exclusively with older F-mount non-DX (full-format) lenses, and the problems could have been present from day one without his noticing. That seems to indicate a problem in the CPU contacts, maybe a complete disconnect. He was just compensating, and didn't realize that the meter was much farther off than it ought to be. The contacts on the body look good. I'm now suspecting that I just didn't notice the AF/VR/Aperture-control problems when I mounted the Tamron for a couple of minutes initially. All that I really verified was that the shutter worked - and if the metering issue is what I suspect, that the aperture is diving to its smallest level on every shot without the aperture servo setting the required opening, then the fact that the first test shots were in bright daylight would not have shown it. The CPU lens contacts on the body appear clean and pristine with a strong magnifier, in at least as good condition if not better than those on the D60. I suspect that this guy had a body that was faulty from day one, and never snapped. If I had to take an initial guess, I'd be looking for the ribbon cable from the contacts to the body's circuit board to be improperly plugged in, pinched, or damaged. It's apparent that the electronic functions in the lenses are not being driven from the body at all. Ribbon cables are infamous sources of Issues; the electronics themselves tend to be pretty bulletproof, though there are always exceptions. Eh, if I can find a repair manual, I may attempt surgery on this myself. I've fiddled with things at least as delicate and painstaking in the past. If it's just an unplugged cable, that's easy to correct.

One addendum: In the interim, I had tried a different Nikkor 18-200 of questionable state of functionality, and nothing on it appeared to work at all. I can't think of a way that briefly mounting a nonfunctional lens on the D300 might have bollixed its works, but people more familiar with the internal tech might.

I recently picked up a used D300 body and a used 18-200 VRII lens to use with it. When the body arrived, I checked basic functionality using my old Tamron 18-200 AF (non-VR) lens, and the autofocus seemed to be functional. Today, the used Nikkor 18-200 VRII arrived, and now the D300 appears to have no AF functionality at all. The seller reports no known issues with it in this area, and there are other areas of wonkiness apparent as well; auto ISO produces images that are multiple stops underexposed. Compensating with a +5 exposure compensation produces an acceptable result, but that much should not be needed outside of unusual situations. I have already tried restoring the factory defaults for all settings, updating the firmware to the latest version (from 1.10 to 1.11) and carefully checking the position of all switches on the body and lenses; nothing is set in a manner that ought to cause AF to be nonfunctional, but that's the major issue - with the need for EV overcompensation second. I'm leaning toward a diagnosis of "Body needs professional attention", but given that such devices often have Known Quirks which can be dealt with less extravagantly, I'm hoping that people with more experience will be able to point me at the necessary magic if it exists.