Nikon F2 Photomic DP-1 aperture not coupling properly

[nicholasnicholas]

Hi all,

Hoping someone in the Nikon F2 know has some ideas on this one.

I just got a new (to me) Nikon F2 w DP1 and put a lens on, clicked it to smallest and largest aperture to tell the meter what to do. Looked in the finder and the aperture readout doesn't match at all. When set to f5.6 on lens it reads f22 in finder, f16 on lens reads as the largest aperture and a white circle. The lens readout won't go down lower than f5.6 even if the lens is @ f2

Meter needle moves so that shows power to the meter works, but doesn't seem accurate.

The prism was a bit beat up, could it have been knocked out of alignment inside?

Am I missing something in the setup, I hope there's a fix, it's a great camera.

Thanks!

 

[KinoGrafx]

Hi- I’m pretty sure the aperture readout is controlled by a string/pully system (like some nikkormats) so it sounds like something has broken or slipped. There’s a teardown detailed here: http://ss-it.de/data/finder/F2 Finder DP-1 Adjustment.pdf

 

[BradS]

Has the lens been mounted correctly?
Is the aperture follower pin in the finder properly engaging the rabbit eras on the lens?
After you do the "Nikon shuffle" what aperture is shown in the little max aperture window on the front of the finder above and to the right of the last 'n' in "Nikon"?

 

[mshchem]

You may need to "push" the coupling pin back up into the meter before mounting the lens.

 

[mshchem]

Another thing, happened to me once in using these bodies since 1973. I had one body that had an electrical failure, meter finder wasn't getting power from the batteries in the body. If you have a volt ohm meter you can check for power at the pins on top of the body. These are such wonderful cameras.

 

[nicholasnicholas]

Thanks for the input. I felt confident this morning and opened up the prism.
I could see the tiny aperture wheel that shows in the finder and links in with the aperture pin.
Without removing any gears or pulling complex things apart I did the following:

1. Holding the aperture pin engaged at the widest f stop (1.2/1.4)
2. Carefully turned the little aperture gear / wheel with the numbers to show the 1.2/1.4 mark
3. Let go of the aperture pin and reset to f5.6
4. The mini gear with f numbers when reset matched f5.6

I gave everything a good blow with the air rocket to clean any dust before putting the 2 prism halves together, screwing it all back together and put on the F2.

Low and behold, the aperture on the lens matches in the finder!
Hope this helps anyone in the future with a similar issue. Photos attached.
It's a delicate but not super complex mission!

 

[mshchem]

Good Job

 

[KinoGrafx]

That’s very cool- So is the aperture readout wheel a mechanical/geared linkage (not thread & pully)?

 

[nicholasnicholas]

That’s very cool- So is the aperture readout wheel a mechanical/geared linkage (not thread & pully)?

Indeed, it's all very neatly geared and linked. What a complex system!

 

[LilHam]

Hi all,
I have recently purchased a Nikon F2 with a DP1 finder and seem to be having the same problem as Nicholas from the start of this thread. My internal aperture reading on the DP1 finder does not match what aperture is selected on the lens. I've had the camera for nearly a year now and it's only just started doing this recently so must've been knocked or some wear and tear. I've uncoupled the finder and managed to get it reset to the default 5.6, reconnecting it and it now correctly shows 2.8 on the white box on the front of the finder but still isn't matching internally.
My DP1 light meter seems to be working just fine and the needle moves in seemingly appropriate measures when changing the aperture or shutter speed, it's only the aperture reading inside the finder which is incorrect. My question is - if the meter seems to work fine and I have a good idea as to what aperture on the lens I'm shooting with, does it matter if the aperture reading in the finder is out? Like does the finder aperture reading somehow link to the light meter reading etc, or is this more of a surficial issue which won't actually effect the quality of my photography? Genuinely not sure of the answer so any advice is greatly appreciated!
Thanks

 

[andyvan]

Hi all,

Hoping someone in the Nikon F2 know has some ideas on this one.

I just got a new (to me) Nikon F2 w DP1 and put a lens on, clicked it to smallest and largest aperture to tell the meter what to do. Looked in the finder and the aperture readout doesn't match at all. When set to f5.6 on lens it reads f22 in finder, f16 on lens reads as the largest aperture and a white circle. The lens readout won't go down lower than f5.6 even if the lens is @ f2

Meter needle moves so that shows power to the meter works, but doesn't seem accurate.

The prism was a bit beat up, could it have been knocked out of alignment inside?

Am I missing something in the setup, I hope there's a fix, it's a great camera.

Thanks!

good thoughts, but have you also tried setting the ring on the asa dial (next to the prism, on the prism assembly) to make sure it couples with the body's shutter speed dial, this also sets the asa for the meter too, so if these are not engaged right, the reading will be off, also if the lens \ camera is updated to the Ai system ( the ring on the body lens mount + the pawl on the ring) this pawl must be lowered to engage "stop_down metering mode" ie to use the lens ring to select the settings and close the iris ; if not down, the prism communication link is removed, so can't follow the aperture ring motion. Also the pin can be on a fusee chain link like on the pentax 67, which if 'man handled' can break, causing this miscommunication.
one final thought, these meters are cds, aka a comparative meter, if, like most they get old, and as the "reference" voltage is based on an isotope, they degrade over time, losing their power output, no longer providing the clean, or correct voltage, so the meter is physically reading the light wrong, as the reference isn't strong enough to tip the teeter totter circuit in the right amount to expose correctly.