[blackcloudbrew]

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After casually reading over the past few years about the Tamron adaptal system, I never really expected to find myself either needing one or needing to get more info on it. However, a week or so I was rummaging around in the VERY used box of photo equipment at my local photo store and was surprise to find a Tamron 28-70 (44A) lens with what looked to me like an adaptal mount. As it fit my k-mount camera, and it was really cheap, I bought it. Then...got it home and the questions started coming. I could take it apart but couldn't put it together, so, I tracked down the manual online and I've solved that problem, but it still works kinda strange. Then in looking at it, I noticed that it was labeled 'R I' on the bottom where it - or so I believe - should be 'PK'. So it fits but my K-5 doesn't want to read the f-stop info from it. Then from the manual I've found online it 'seems' that the PK version has like 3 electrical contacts and mine only has 1.

So the questions are these:

1. What did I buy? Is it the Ricoh mount?
2. Are adpatal mounts supposed to talk to my K-5 or do I just have to use stop down metering with it regardless. I can do that but if it's because I have the wrong mount, I need to know that and go get the right one.
3. Any other useful info for an adaptal nubie would be helpful as I just bought another Tammy adaptal lens for this new toy.

TIA

[Lowell Goudge]

ive not seen an RI mount before, care to share a photo?

as far as mounts are concerned, a true PKA mount will communicate with your camera.

there are also 3 other mounts for pentax, there is a K mount, which works but only in stopped down mode, and there are 2 versions of screw mounts, one with open aperture metering for the spotmatic F and ES II and one for auto aperture only.

just as an aside, have you put the lens in A mode or in F32 using the A button.

it will only work with the body controlling the aperture in A mode, otherwise it works just like a K mount

[blackcloudbrew]

I found a shot on eBay of what mine looks like and so I conclude that mine is a Ricoh mount. Note the one contact and the R I labeling on it.

Tamron Adaptall 2 II mount Ricoh PK | eBay

[Lowell Goudge]

it will work like a K mount, with green button stopped down metering. the pin itself looks big enough that it should not give any issues where it can fall into the screw drive on the body and get stuck.

it is worth trying to get a KA adaptor because then your flash will also work along with the automatic modes of the camera

[Doanh]

You can find a lot of useful information here: adaptall-2.org. According to the website, the lens is pretty good.

Your lens is Adaptall-2 so if you can find a PKA converter that works then you can use like the A mode.

[blackcloudbrew]

Thanks both of you. I know about the adaptall-2.org site but could not directly find the info there - yet - I was looking for. I clearly have some more reading to do on this.

[hoanpham]

i have a few tamron adaptall lenses. The primes and zooms in SP series are very good.
You may not need the PK/A adapter since it uses to go for very high price, and many not in working order.
A PK/M adapter is cheaper, reliable, but you don't have features like A-series lenses.

These adapters also work with older adaptall lenses (first version)

[excanonfd]

It looks like you have the Ricoh mount version. Try shooting with it in M mode. Even if A mode is unavailable, M mode should work just fine.