Tamron Macro 90mm not working with Macro Tubes! Eh...?

Just been playing with the Tamron 90/2.8 Macro 1:1 SP Di that we bought today at SRS, and one of my first ideas was to put it on the end of my macro tubes, just to see what level of magnification I could get!

But it won't work!! The shutter just will not fire!

It's on manual focus.
Tubes work fine with my DA*50-135 & DA*16-50
Shutter fires fine with no lens, tubes only or lens only.
Tried the 50mm 1.4, that won't fire on the tubes either!

The tubes seem to fire fine with my zooms lenses (never had a problem before, sure I have even tried the 50mm on them fine before), but not fire with the 2x primes. This is where i went 'Eh...?'

Hopefully its just some simple setting that I have missed, but I have no idea what?!

Anyone have any ideas?

Cheers

Danny

OK, weird time again, just put my 1.4x teleconverter on the camera body 1st, then the tubes, then the lens, it fires!

Have you tried cleaning all the contacts? Ought to work so long as you have definitely set the body to MF or AF.C

Yup, fully cleaned just in case, body on MF!

Half press, doesn't give focus confirmation either.

Read my post (third from bottom of page 1) in this thread. It has helped others, it might solve your problem.

Would I still need to give that a go if my tubes have all contacts already? The * lenses have more contacts than the Tamron, and they work fine, so confusing!

At work all day, so will try when I get home!

I took Pete's advice and it worked for me.
My Jessop tube only have 6 contacts so i scraped the paint where the seventh would be and it worked like a charm
Thats if you are having the same problem i was having.

Possibly. When you say the tubes have all contacts, do they have as many contact's as the body? I'm guessing they don't.

The Tamron's bayonet mount is presumably chromed steel and will give a good electrical contact with the body. When you put the tube(s) between lens and body, you could be insulating the 7th pin from the body, not the lens ('cause it doesn't have one). I believe that 7th pin is simply an electrical ground. Certainly if your tubes are Jessops, you will need to remove some paint as in Clarky's pic above. It's not an ideal solution, but it works.

When I did mine, it worked even with all three tubes between camera and lens. Essentially, you need electrical continuity between the 7th pin on the body, to the bayonet mount of the lens.

I did eventually sell my modified Jessops tubes to a forum member and bought a set of Kenko tubes believing them to be proper A/F tubes. They have all the pins, but M/F only . Another waste of money.

Good luck with it.

Right, home now, just checked and the tubes definately have all 7 contacts. Clarky's pic seems to show six pins, with paint scratched off where the 7th would be, but because mine have all 7 pins, not sure what to do?

Nor me. How many tubes? What make? Do they all behave the same? Do they behave the same on your old K10D? Do you have a DVM to check electrical continuity between front and back? Post some pics of a tube front and back.

They are the Jessops ones, which I believe were made by Kenko?

They look identical to Clarky's, just with the full 7 pins.

Have now done what was recommended, and so far am managing to get them to work!! But it is getting weird again, 2 working, one not. Will persevere!

Also I get the feeling that these with 7 pins are unusual?

I did exactly the same thing pete
My new Kenko tubes have the AF slot on the mount but for some reason the AF screw on the body doesn't seem to marry up with the AF slot on the tube : :

Unlocker. I am not sure what you have there : Do they say Jessops on the side of each tube :
These may be a later release with an added contact but may also be of poor quality.
You say you got 2 of them working so it appears you are on the right track.

It's goinf to be a tolarence issue then. Spring pressure, depth/height of contacts, diameter of contacts. Something like that.

Have you tried them on your old camera?

Success!! Just needed to scratch away a bit more!

Many many thanks to all your help guys, appreciated!

Thought I would have a quick go at the penny, need more tubes! Also a couple of tube pics!

Excellent. Another satisfied customer. Now perhaps you can help me unlock my phone.