Tamron Adaptall-2 46A vs. 158A Screwup

[guardian]

There are worse things, I'm certain. But it's not fun when you suddenly realize you don't know what you don't know.

It happened to me earlier today. I like the Adaptall-2 lenses and use this as my Bible for the non-SP lenses:

http://www.adaptall-2.org/lenses/Adaptall-2_LensIndex.html

So when I bid on and won a Tamron Adaptall-2 70-210mm lens recently on eBay, I assumed I had bought a 46A:

http://www.adaptall-2.org/lenses/46A.html

The lens showed up. It's not a 46A. It's not a 58A, either:

http://www.pentaxforums.com/userreviews/tamron-adaptall-2-70-210mm-macro-f-4-5-6-58a.html

And I had never even heard of the 58A. The lens I received, instead, is a Tamron Adaptall-2 158A. And, no, I had never heard of that model, either!

Now to be clear, these are plastic lenses and that's what I wanted. I wanted something light for my Olympus E-PL1. But now I have a lens about which I know nothing optically. The 46A, optically, was (to me) fine. Is the 158A equally good optically? I don't know. I can't locate much information on the 158A regarding resolution.

Bottom line I messed up. I didn't know what I didn't know. Heck, I was under the impression no Adaptall-2 lenses had been manufactured in the twenty-first century. That is wrong. Again. I'm very disappointed regarding the Adaptall-2.org website. I assumed it was all-inclusive. I should not have assumed.

So now I have an Adaptall-2 158A lens about which I know nothing. And it's not the fault of the seller. It's all on me.

[ManualFocus-G]

The 158A is totally different to the 46A and no-where near as good. But...it is MUCH smaller!! I made the same mistake when I first started out, thinking it was a 46A (not reading the auction properly). I believe the 158A and 58A are the same, or extremely similar if not.

Here's some samples from the 58A:















And from the 158A:







And from the 46A:





More: http://forum.mflenses.com/tamron-ad2-70-210-3-8-4-46a-another-superb-budget-zoom-t20904.html

[guardian]

ManualFocus-G

Groan. Well, I appreciate your kind reply, anyway. And it's a lovely set of photos.

But I am disappointed with myself. Live and learn? Yes, I guess that's what this is about for me.

I was holding out hope Tamron might have maintained optical quality and resolution on the modern version of the lens. Silly me.

Will I be more careful in future, and be certain of Tamron model number before bidding? Count on it.

[luisalegria]

The adaptall-2 site is incomplete in most of its sections, both old and new.
Whoever built it originally put in a lot of excellent work, but it was never finished.
I have or have seen undocumented Tamron lenses from most periods.

[nemesis101]

Yes nice pictures though they do show one of the weaknesses of the 58a / 158a namely CA.. I feel your pain as I have all the varieties of 70-210 that Tamron made with adaptall mounts, both SP and standard grade, as well as two with adaptamatic fittings (the pre-cursor to the adaptall idea)

THE one to have is the f3-5 19AH, but I also have a high regard for the auto-focus built-in version too!

I've posted pictures taken with the latter here on the forum.

Doug

[guardian]