Tamron 2x TC on Nikon D50

[mike_tx]

Hi,
I just purchased a Tamron 2x TC for use with my D50. However, I can't get it to work with any of my lenses. Here is what I've tried:
- Nikon 18-55 (standard D50 lense). D50 screen shows "F - -"
- Nikon 55-200 VT (screen shows "F - -"
- Tokina 70-210 (older lense....shows "F- -")
Nikon 18-70 ("F- -")
Sigma 35-70 (older lense....my worst lense): partially works (AF hunts around and can't figure out a proper focus, even outside in bright light).

Should I just give up? Any tips or tricks? Is it possibe that the TC is broke? I know most TCs require more light to have AF work, but why am I getting the "F- -" message?

Thanks, Mike

[Daniel W.]

The "F--" means the camera can't register the aperture, which may be an issue of electronic contacts or the physical build of the lens.

Not to answer your question directly, but to stick a 2x TC on each of thoses lenses you listed is a big reducer of quality. Folks stick a 2x on the top of the line 70-200 and super tele primes and complain... (but I hear soft-focus is coming back into style so who knows.)

[tc95]

Mike....there might be a problem with the number of contacts the TC has...it might not have enough to let the information pass from the camera to the lens and vis-a-versa....

I had a Tamron SP Pro 1.4x/2.0x/3.0x that worked with my D70/D90/D300 when I had a Nikon system...but the SP has eight contacts on the camera side and 10 contacts on the lens side...if your has this...you should be good...and if it does not work the TC may be bad...if you put the camera in M-Mode (Full Manual) you should be able to work the lenses with the TC just not Auto-Focus and you will have to set the cameras ISO/Speed/F-Stop manually....and use the F-Stop ring on the lens...

Good Luck...hope this helps a little...

[mike_tx]

The Tamron I have (Tamron-F AF TC, 2x N-AF BBAR MC7 S) has 7 contacts on the camera side and 7 contacts on the lens side. My D50 only has 7 contacts, so I would think it would work. However, I did notice that my 18-55, 55-200 lens have 10 contacts.....why? Seems like 3 too many.

So I ran a few more tests: I also have an older Sigma 24mm f2.8 lense: that worked fine...focuses, etc... I have an older Tokina 70-210.....won't even fit? I can't get it to mount....really strange.

Mike

[revjvegas]

Don't you loose a couple of stops when attaching a TC?
And if that's the case, it might explain why they are only recommended for use with f/2.8 or better glass. Or at least I'm pretty sure I've read that somewhere a while back.

Might be a possibility.

[tc95]

The Seven contacts that you see...deal with the information transfer as you know...I would think the extra 3 pins, deal with the AF-S focusing...and better handling of the VR functions with Pro-Sumer and Pro bodies...also might be redundent communication for older bodies...

Here is a pinout diagram...it does not tell you what everything is for....but the 5 pins it does show...are Distance/Zoom/Metering/Power and Ground...

This is taken from Foolography...TC16a mod to newer bodies......Hope this helps a little....