Which contact does what on Nikon lenses?

[Karhallarn]

Hi guys,

after I saw some people here chipping their old MF Nikkors, I wanted to ask a question.

Which contact is supporting autofocus on Nikon DSLRs?

Backround is, I have an old Sigma AF 75-200 f3.8 lens. The lens does autofocus in normal state with my D200 but really sluggish and the metering is off by to many steps to count, because of the aperture shown as f1 all the time!

Now I disassembled the contact and without all of them, I put in the aperture via the lens data option of the D200 and the metering is spot on but the autofocus doesn't work!

I think I tried all possibilities of combinations and I found out that the second contact from the left has to be missing to let me put in the aperture manually. But in this configuration, the autofocus doesn't work at all. Is there a way to get the autofocus working but take the aperture from the custom option?

cheers in advance,

Karhallarn

PS: Sorry about the lens being autofocus but this forum is the best source I when it comes down to working on a lens!

[Scheimpflug]

I too would be interested in the specifications of this interface, should anyone know.

[sdjensen]

These guys make the dandelion chip and they should know which contact goes to what.

http://filmprocess.ru/nikon_spec_en.htm

Btw you can buy the chip from here http://www.leitax.com/leica-lens-for-nikon-cameras.html and it works like a charm.

[Gurdie]

Maybe these links help, I don´t understand anything of them.

http://photo.net/nikon-camera-forum/00Rop6

http://www.foolography.com/free-stuff/modify-tc-16a/

[Karhallarn]

Cheers guys!

@ gurdie: I already knew the first one! If sombody can explain the abbreviations to me, I would be gratefull!

The second site looks very promising! I will work myself through it and tell you if it did the job?

ciao,

Karhallarn

PS: In the meantime, I have removed the first two contacts and the metering is spot on now but it seems the autofocus need all 5 contacts.