Tamron Adaptall SP 35-80mm question/observations

[awa54]

A nice clean example of the SP 35-80mm zoom just arrived today with an M42 adapter fitted (I count the lens purchase price as being discounted by $25, since I was going to buy an M42 adaptall some day anyway) and it has already been mounted up to the a900 and had a brief walk-around session on my lunch break.

So far it seems like this is the best of the Adaptall era Tamron zooms I've tried (28-50, 35-70 f3.5, SP 70-210 f3.5), especially where flare and contrast reduction are concerned. It seems to have pretty even performance from end to end and decent sharpness wide open, increasing to very good when stopped past f5.6. I'm also impressed by the fact that it only has slight to moderate linear distortion, only showing obviously at the wide end and then not much more than primes of that era. It even seems to have really good background bokeh, the foreground is a bit busier, but still not terrible. The only low point is blue fringing on burned out highlights, which is noticeable when viewed at higher magnification, but not distracting even at full screen size on a 17" laptop.

Now for the question... is the slightly loose zoom ring a "feature" (read quirk) of this design? I located the retention screws with a magnet and carefully slid the grip rubber back (damn, Tamron used good materials for that, it's still pliable and grippy decades later!) until I could see them, it looks like maybe the screws float back and forth in slots in the ring? At any rate none of the philips screws accessible through the ring cutouts were loose and the slot head screws that the ring drives were snug as well, so I'm assuming that all is functioning as intended.

I'm looking forward to getting to know this lens better!

[DxD]

My SP 35-80mm zoom has the same looseness (half a millimetre or less). I bought it in 1981, and I don't think it had that looseness originally.

Despite 25 years of use, including walking, skiing and bike riding trips, this lens still gives results which are very sharp and the macro is excellent. I have a number of more recently purchased Olympus and Tamron zooms of the 1980s and the Tamron SP 35-80mm is undoubtedly the best of those 1980s lenses that I have tried.

[cooltouch]

I have a Tamron SP 35-80 which I bought a few years ago, expressly because people here at the forum heaped such high praise upon it. So I figured I needed it in my collection. However, I've only used it a few times. Not because of any complaint of the quality, more is the case that I just find 35mm at the wide end not as useful as a lens with 28mm or 24mm at the wide end -- and this is shooting with film cameras. My digital is an APS-C, so 35mm is about like a normal lens at that aspect ratio.

Still, one of these days I'll have to make a point of taking a film camera out with that lens only and a fresh roll of fine-grained film and put it through its paces.

As to your question about zoom ring looseness, I just examined mine -- which is a pristine example, I gotta say -- and there is no looseness with the zoom or focusing rings. They are quire easy to turn, however, but I wouldn't consider this ease "looseness." It feels very smooth and well-engineered, if you ask me.

About the screws you found -- different zooms employ screws differently. I'm not sure what Tamron does. Vivitar, for example, with their Series 1 wide to tele push-pull zooms, like the 28-90 and 28-105, have screws that fit into bushings that are threaded into internal tubes. These screw-fastened bushings ride through slots in other tubes that are cut at various angles and which control how the optics move about as you zoom in and out. Tamron may do something similar to this, but I don't know. If they do, then in order to get rid of the slop, you'll most likely have to open up the lens and lubricate the passages that these screws (and whatever they're fastened to) are moving about.

[RnR]

Also a slight loose feeling in the zoom ring on my copy. Focus ring has a solid tactile feel.

[awa54]

To clarify, the "looseness" isn't in the lens movement, rather the zoom ring only... when turning the ring there is no slop in movement or coupling of the ring to the lens, but you can rock the aluminum ring body a fraction of a millimeter back and forth on the lens barrel.

I wonder if there was a flocking gasket/bushing inside that ring at one time to prevent this condition and it has compressed or decayed, could also have been a rubber shim around the interface screws maybe?

[cooltouch]

Okay, gotcha. I just checked mine again. No zoom ring displacement.

Since you removed the ring's rubber sleeve and you checked the tightness of all the screws you could find there, then, yes, it appears that it would likely be the way the ring is riding on the lens barrel. Flattened flocking sounds plausible. I dunno offhand what else it could be, other than perhaps heavy wear or abuse causing the ring to lose its tolerances.

[Oldhand]

Mine has the same little bit of play fore and aft but only in the bottom of the ring - ie 180 degrees to the focus mark.
The upper part of the ring at the focusing index is firm.
Doesn't affect operation at all and probably as Michael has said - wear and tear from use. The lens has to be forty or so years old

Tom

[marcusBMG]

The 01A is a bit notorious for developing play in its mechanics with age and use. If you are lucky you can find one that's still "tight". More commonly there is a bit of play noticeable, the in-out play of the focus section is typical, also can be play of the zoom ring and mechanics. Bad ones will have pronounced play which can cause focus difficulties (shifts out of focus with tilt) and affecting the mechanical movement into close focus which simultaneously moves the zoom (tends to stick).
The OP's example doesn't sound bad - minor mechanical fault, shouldn't be a problem.
I have a couple of these that I intend (eventually) to try to dissasemble and tlc. There is a ring that unscrews to release the focus section, this requires a diy tool.

[awa54]

[awa54]

Hah!!

it *is* a "feature"... turns out there's a threaded ring that controls tension on the zoom ring. I noticed that the forward lip of the ring wasn't rotating with the ring and that it has two slots where a spanner can be used, I don't have a correct tool for that, but was able to tighten the ring with a tool in only one side. Now I have firm zoom tension and no slop in the zoom ring!

[cooltouch]

Yay!

Thanks for the tip. I'll keep it in mind, should mine ever need tweaking.

[SkedAddled]

I would imagine the lens is similar in construction to the SP 28-80, of which I own 2 copies.

I don't experience any untoward play in either of my copies, one of which is nearly pristine,
and the other showing some outer wear.

You're certainly correct about Tamron's rubber grip sleeves;
they're holding up exceptionally well on both of mine, as well as on my
SP 60-300, which has an enormously-long sleeve!

I'm glad you straightened it out, at any rate.

[Black Elk]

Good day.

My name is Vaughan Kennedy and I live in Northern Virginia. I did not see a new member intro thread. I have a Sony NEX-6 and a Sony a6000. I recently acquired a Tamron SP 35-80mm Adaptall2 01A lens. I have a question. Does anyone here know where I can find a copy of the original operating instructions? It is pretty intuitive on how to use the lens. However. I want to gain a better understanding of items such as:

The orange, green, and white coding/lines as well as the data on the lens barrel.
The AE next to the 32.
The little R at the base of the lens barrel.The small orange and green marks right above the aperture ring.
The green dot below the aperture.

Any assistance you can provide is greatly appreciated.

Thank you,
Vaughan

[visualopsins]