Adaptall mount problem with Canon body.

[waynecrider]

I have a problem with an Adaptall mount on a Canon FTB body. I just received this combo thru auction and the lens doesn't stop down. I got the lens off the mount and took a look at things and I think the mount is wrong for the lens. It's an Adaptall 2 and the lens is an AE Tamron 24mm F2.5. As far as I can see, the actuator in the mount will lineup with the aperture actuator linkage in the lens when you line up the dots and push the lens into the mount in preparation for locking it on, but when you turn the lens to lock it in, the lineup disappears so there's no stop down. On top of it I checked the lever in the cameras body which is suppose to push on the Adaptall's lever which in turn pushes the aperture linkage and there is no camera body lever movement at all. Is the mount correct, lens wrong? I think the body lever is broken because the lens/mount lineup is wrong.

 

[David A. Goldfarb]

The green dots should line up between the mount and the lens, and then there is a tab on the outside of the mount that fits a depression on the lens that should line up. Do you have the tab lined up?

Also, be sure the camera isn't in stopped-down mode when you attach the lens, and if I remember correctly, the lens shouldn't be set to AE when you attach it.

 

[waynecrider]

No luck David. I align the green dots, the black lever is in the lens slot and turning the lens to lock it causes the actuator lever to ride up on the lens mount and there's no contact to the aperture linkage. Maybe I'm installing it wrong, but I have been over it a dozen times trying everything. Turn the lens, no linkage contact. Lens and mount both Adaptall 2.

 

[Peter Black]

Ok, from the leaflet I have in front of me, the Canon mount is not one of thise that need special instructions, so here goes.

Attaching the mount to the lens:
A. Be sure to set the aperture ring of the lens to the maximum aperture.
B. Align the green dot on the base of the lens with the green dot on the adaptall-2 mount
c. Press the mount downward and turn clockwise until the mount is locked into place (while turning, the silver release button will slowly depress and then will open and click when the mount locks into position)
D. Slide the coupling key of the mount (tab that David speaks of) into the matching slot of the lens aperture ring. Sometimes the coupling key will slide into the matching slot after step C and therefore this step may not be necessary.
NOTE: some mounts have 2 coupling keys. If the custom mount you own has 2 coupling keys, be sure to engage the 2 keys onto matching slots on the lens aperture ring.
It can now be fitted to the camera.

Hope this solves the problem, and you may like to know there is a website dedicated to the Tamron lenses, although the mount part isn't posted yet.

http://www.adaptall-2.com/

 

[waynecrider]

I think I figured it out. I was looking at the wrong linkage on the Adaptall. The lenses aperture linkage is a rider cam that is actuated by a push block at the bottom of the mount. It is apparently either stuck or broken so the adapter will need to be replaced. Thanks for the help.