Michael R Freeman

See Roland Vink's site. Nikon Lenses Serial numbers 2050001 - 226xxxx of the 50/1.8 pancake produced for the Japanese market. More than just cosmetics. While the optics may be the same/similar, having CLA serviced multiple copies of each and every version of the Ai/AiS 50/1.8 I can confirm that internal construction is quite different from all other 50/1.8 models. NIKKOR 50mm 1:1.8 S AIS 2257006

BNIF (Birds not in flight) ...;) D750, AF-S Nikkor 50/1.8G SE

Morning lake mist. D7000, AF-S DX Nikkor 16~85mm @30mm

There is also a difference in minimum focus distance. The 50/1.8s pancake in Dieter's link above (originally sold only in Japan, s/n 2050001 and up) has a 0.45m minimum focus versus 0.6m for the Mk.II chrome ring version of the Series E (s/n 1900001 and up). The final version of the AiS 50/1.8 Nikkor exported worldwide (s/n 4000001 and up) shared the 0.6m minimum focus of the Series E. There are also differences in internal construction. The Japan 50/1.8s pancake has all metal helicoids. The chrome ring Mk.II Series E (and final AiS 50/1.8 Nikkor) has metal (3) and plastic (1) helicoid threads. The Japan pancake and Mk.II Series E has a metal focusing ring. The final AiS 50/1.8 Nikkor has a plastic focusing ring. The Japan pancake has a metal aperture ring, the other two have a plastic aperture ring. See Roland Vink's excellent database here: http://www.photosynthesis.co.nz/nikon/lenses.html#50slow

Late November sunrise. D7000, AF-S DX 16~85mm VR

I have seen this as well. As Matthew noted, only suitable on certain early Nikkors where the rear skirt of the aperture ring would not touch the AI tab. There isn't actually enough material extending beyond the bayonet mount on these particular aperture rings to mill a notch to engage the AI tab for a John White style conversion.

Nikon D7000, AiS Nikkor 300/4.5 EDIF American Black Ducks

Yes. A lot of surface area on all those helicals. A very light grease and very little of it is required for smooth focusing. In my limited experience, it's the rear CRC group helicals (lower left) that are responsible for the very stiff focus (and sticky oily aperture blades) in a 55/2.8 lens that requires service. Bought one years ago for next to nothing that was literally locked up tight, but focused beautifully after a cleaning and relube.

Agreed. As noted, unless you have a secret parts source located at the end of a rainbow guarded by a tiny leprechaun for a lens that was discontinued 35 years ago, your only likely source for a rear element group is a donor lens. And if you're going to try to find and buy a donor lens, you might as well buy a good fully functioning lens. I doubt they are very expensive. Chances are also good that any lens with the severe impact damage shown in your photo has other hidden problems. If you want to have some fun, take a look at Richard Haw's directions here and see how far you can break this one down before you give up. ;):) Repair: Nikon 70-210mm f/4 Series-E

If the aperture assembly is deep inside this lens, then it might have very long mechanical linkage(s) attached to the aperture ring that could make reassembly tricky. My guess is that the aperture is between the 3rd and 4th elements when viewed from the back? If you remove the mount screws and slowly lift it straight off, you will probably be able to see what is directly attached to the aperture ring. Might be a simple "fork" engaging another lever, or it could be a long lever fixed to the aperture ring reaching deeper into the lens. AF-S Nikkor 500mm f/4D IF-ED II

It might not be "pro", but it's a robust and very well made DSLR with magnesium alloy body construction and a bright pentaprism viewfinder, shutter is tested to 150k cycles, it can autofocus older screwdrive AF/AF-D lenses and it meters with non-CPU manual focus Nikkors. In short, a great camera for beginners or even advanced amateurs who don't need or want the latest and greatest. And if I read the OP's post correctly, it was FREE! Can't go wrong with that. :)

Absolutely. If you already own it, shoot with it, have fun with it. It's not the latest and greatest, but it's still a very capable camera. Truth be told, its capabilities probably exceed the needs of most people who still own one (myself included). Although I have not used the AF-S 18~105, it is a good lens for a beginner with a nice field of view from moderate wide angle to medium telephoto. I recently updated to FX with a D750, but I kept my D7000 for 300mm and longer telephoto use.

Erik Lund over on the NikonGear forum also added a Dandelion CPU chip to an AiS 50/1.2 about 5 years ago for Bjørn Rørslett. If I remember correctly, it involved milling a relief in the rear lens element!

It can be CPU chipped, but it's not a DIY project. And not inexpensive I would guess. :-) The Unicorn CPU Nikkors: 50 and 55 1.2s

Hopefully you have a bad flash. The fact that it wakes up from standby mode and you are getting a flash ready indication in the viewfinder indicates that at least the F4 is communicating with the flash. I have a less than favorable opinion of the SB-600. The one I used to own failed twice. Official Nikon Canada unit. It would randomly not fire (on a D200), eventually to the point that it would not trigger more often than it would successfully fire. Sent it in to Nikon Canada and they repaired it. Forget what they replaced but it was a major repair. Used the repaired flash (now on a D7000) for probably less than 6 months after it was returned to me when it failed again, this time completely. Would not fire even off camera with the test button. Tossed the damn thing in the garbage and bought a new SB-700.

A long shot, but do you have the ISO set manually (i.e. not set to "DX")? Suspect if you have it set to DX the SB-600 may not fire when in TTL-BL mode if it doesn't know the ISO.

A couple of things you might want to try: Take a cotton swab (aka "Q-Tip) wetted with isopropyl alcohol and clean all of the flash contacts on the hot shoe, including the ground (springy bit under the edges of the flash shoe mount). Pop off the viewfinder and do the same for both the gold contacts on the body and the pins on the underside of the DP-20 viewfinder. I would suspect the chance of this is pretty remote. The F4 flash sync system is good for up to 250v if my memory is correct. Good luck. (I miss my F4 ... fond memories of shooting with it)

I would skip the F70/N70. Has a weird (to me anyway) user interface like no other Nikon camera. Designed by a Nikon engineer who was also a closet Star Wars fan me thinks.:);) F80/N80 is the best of the 3 you listed. When it was offered new, it was the top of the line consumer film camera in Nikon's lineup. F75/N75 was the next lower tier camera.

Modern Nikon F mount looks like this ...

Sorry, but this lens will not fit your camera. You have a Canon EF mount Sigma lens (Canon EF lens mount - Wikipedia). You need a Nikon F mount to fit your D5000. Canon EF mount

OP is in Canada. Nikon USA will not ship parts to Canada. The Nikon Store can only deliver to postal street addresses in the 50 United States and District of Columbia. If Nikon Canada offers an online parts store, I can't find it. :(

I don't have an FM body to open up, but I do have an exploded parts diagram from an FM repair manual. Not sure if it applies to your serial number range, since if my memory is accurate, there were 2 different marks of the original FM series bodies? Anyway, part #464 in the drawing below is the lock lever on the FM. Hope that helps.

Yes. No duty. HST/GST only plus a handling fee if importing by the postal system. Don't recall what the handling fee was exactly, but it is a fixed cost and not related to the value of item. $15 or less I think.

Absolutely. ;)

Agree with Rodeo Joe that slop in the focusing helicoid is the likely source of your problem. While I have not serviced the 55/1.2, I have CLA'd many early Ai lenses from 24mm to 200mm, and a few pre-Ai models. All had helicoid keys that allowed the backlash in the focusing ring to be adjusted (the later AiS series have no such adjustment) . Either the key itself is adjustable (split key shown below) or if the key is solid the groove it rides in can be adjusted. If the backlash is really sloppy, or more likely the very tiny screws holding that small split key are loose, it will slightly bind in the groove when focusing and when it breaks loose the focus will jump. These early lenses have a very robust internal construction, so I would expect that a simple CLA will cure the problem.