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Tamron Adaptall-2 SP (31A) 200-500mm F5.6 Review RSS Feed

Tamron Adaptall-2 SP (31A) 200-500mm F5.6

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6 49,615 Tue February 27, 2024
Recommended By Average Price Average User Rating
100% of reviewers $373.90 8.33
Tamron Adaptall-2 SP (31A) 200-500mm F5.6

Tamron Adaptall-2 SP (31A) 200-500mm F5.6
Tamron Adaptall-2 SP (31A) 200-500mm F5.6
Tamron Adaptall-2 SP (31A) 200-500mm F5.6

"...completely new optical design for the model 31A. Design parameters were an adequately fast F/5.6 aperture for easier focusing with split image and microprism viewfinders, superior reduction of chromatic and spherical aberrations, and superior resolution and contrast across a very flat field. "

This large and powerful 2 ring telephoto zoom introduced in 1984 superceded the earlier f6.9 designs and was produced to compete with OEM lenses. It was in production till 1992 and was the most expensive zoom adaptall. Its f5.6 constant max aperture can be considered pretty fast for 500mm (but not for 200mm!). It is designed with a slot-in rear filter, IQ is in theory reduced slightly if one is not in place. The lens has built in large hood and heavy duty tripod mount; use of a long plate or similar is important to achieve balance when the lens is tripod mounted (an improvised set up using a cheap macro rail is illustrated in pic 2, and you can see a diy'ed plate in pic 3). There is more discussion of this in the lens sample images thread.

Note that he PKA mount, when used with this lens in Av mode with a Pentax camera, will show f4, not f5.6. This is just a technical limitation of the mount. In practice it otherwise works as it should in spite of the incorrect f number reading. However you can make the mount register correctly f5.6 by placing a piece of insulating tape between the two contacts on the mount see pic here.

Focal Length (mm): 200-500mm
Aperture Maximum: 5.6 constant
Aperture Range: 5.6 - 32, AE
Optical construction: 10 groups/14 elements
Minimum focus distance: 98.4" /2.5m
Magnification Ratio: 1:3.5
Filter size: 95mm (front), 43mm (rear)
Diameter: 4.1" (105mm)
length (at infinity): 14.2" / 36cm
weight: 2.72kg / 96 oz.
Lens Hood: Built-in, retractable

Accessories: hard carrying case.
Accepts all the adaptall teleconverters.

There are detailed reviews with comparative images and crops on the "Making Not Taking" blog, by Dave Tameling, and on forum here, by SXR_Mark, and here, by cooltouch; and here, also by cooltouch.
Mount Type: Third-party (adapter required)
Price History:

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New Member

Registered: December, 2023
Posts: 13
Review Date: February 27, 2024 Recommended | Price: $170.00 | Rating: 9 

Pros: Focal range that is awesome, FAST at 500
Cons: Heavy, tough to hand hold, mine is missing the 43mm filter holder

I drooled over and lusted for this lens in the late 80s. I used one in the US Navy, as well as the 300 f2.8, and 55B 500mm mirror.

I'm a retired Navy photographer. Got away from photography after I retired in 2001. A good friend dragged me back into photography for the fun summer of 2022, and since I had some K mount lenses still, decided to buy a Pentax K200D. turns out the old lenses I used for my Ricoh KR30SP and XR-M have that odd Ricoh pin, rendering them useless essentially. I needed lenses and I'm a cheap guy. After buying a couple non Tamron lenses, I remembered these wonderful old lenses and hit Ebay. Call it GAS (Gear Acquisition Syndrome), or LBA (Lens Buying Addiction), either way, I've bought more than I planned to, and at least, I'm not paying for all new gear.

Story time over. Said friend, took me out for some wildlife shoots, wild horses, antelope, bison, owls and coyotes. Loaned me one of his spare Nikons but none of the big glass he used, except when I was out with him. I had a blast, and got hooked. As I work in the desert, I get to see wildlife all the time, and never thought to take a camera. That has changed...

I originally bought the 60B 300mm F2.8, and had some fun, but wanted more reach. I remembered the sharpness of the 31A and was shocked how "affordable" they had become. Purchased for $170 off Ebay, my example didn't have the 43mm filter holder. No idea how long the lens had been open like that. But surprisingly, has very little dust in it. No mold, mildew or fungus, no hazing. Focus is smooth and fairly tight, zoom is very smooth. As with the 60B, I added a front UV filter (95mm) and a new lens cap. the friction fit lens cover is nice but gets in the way when out and about. The lens did not come with a hard case, sadly, but for the price I paid, I'm happy.

OK, lens is heavy. Tough to hand hold. But I knew that. I added a 120mm Arca Swiss plate to the tripod leg to better balance it. My hand rests under it just fine and I seem to be able to use the focus ring just fine. A monopod comes in handy, but a tripod and gimble head is better, the long Arca Swiss plate makes it eay to balance.. I actually have a tough time getting it to focus good. But when I get it, it is gorgeous. I bought the Pentax 1.7X AF Adapter to use with the 60B primarily (Works great with that lens). But find it works pretty good with the 31A, as long as I keep things in the range the adapter will focus for. You will NOT be shooting action sports with this combo. But distance stuff is pretty decent.

As soon as I figure out how to post pics in here I'll upload some. This lens is all that remember it to be. And its better, because I own this one...
Veteran Member

Registered: January, 2011
Location: Houston, Texas
Posts: 982

1 user found this helpful
Review Date: January 2, 2017 Recommended | Price: $219.50 | Rating: 9 

Pros: Very sharp at 500mm, relatively fast max aperture
Cons: size and weight, some chromatic aberrations

The Tamron 31A is one of the sharpest zooms I have ever used. It compares favorably with the Nikkor 200-400mm f/4, a $4,000 lens, which I used to own. It stops down to f/32 and, somewhat unusual I find for telephotos or telephoto zooms, the lens manages to hold its sharpness very well to f/16 and beyond. In fact, I could detect very little change in sharpness from f/5.6 to f/16 -- contrast, yes, but sharpness? Negligible. So this feature makes for a very flexible optic.

The above image was taken with a Sony NEX 7 set to ISO 100, 1/125 @ f/8. The lens was set to 500mm.

This isn't a lens you decide to use on the spur of the moment, however. Nope, you have to make plans when you use this lens. Like bringing along a big enough tripod. Making sure you brought enough pack animals to haul the lens and the tripod. Food for the pack animals, etc.

Okay, so I exaggerate . . . a little. The lens weighs an even 6 pounds (that's 2.72 kilos for you metric-minded folks) Yes, it is possible to hand-hold this lens, but considering its max focal length, you'll want to be shooting at at least 1/1000 second if you do. But pretty soon, fatigue will set in and even 1/1000 second won't be enough to keep the jitters out of you shots.

Here are a few more shots, ones I took today with my 31A resting comfortably on top of my Manfrotto-made tripod with a very large ball head. A neighborhood cat decided to stop by for a while and pose. Kitty was probably 20 meters away and the lens was zoomed out to 500mm.

Here's a shot demonstrating this lens's resolving power. Across the street behind my house, there's a transformer sitting up on a power pole. It's probably about 60 or 70 meters away from where I had my tripod set up. Now, on this transformer, there are a couple metal tags, with various info stamped into them. Let's see how well the lens did at resolving these tags. But first, here's a shot of the scene with the lens zoomed out to 500mm:

And here's a 100% crop of the above image, centering on the tags:

No processing was done to the above image. The camera was a Sony NEX 7, shooting in Aperture Priority mode at f/11, ISO 100.

My copy exhibits a fair amount of chromatic aberrations of the purple and magenta variety, especially against high-contrast subjects. It's mostly gone by f/11, however. Fortunately this type of CA is very easy to remove with the image processing software I use.

It took me a while to find this lens. I would check regularly on eBay for auctions, but all I found were Buy It Now listings, with the typically inflated asking prices. But I was patient. Finally, an auction turned up. It was for just the lens with the front leather cap, and a Nikon Adaptall-2 adapter included. No case, no filters, none of the stuff that came with the lens when it was new -- except for the front slip-on cap. Now, cosmetic-wise, it had some wear. Nothing excessive, but it had obviously been used a bit. The glass was perfect and there was no dust in the interior.

I don't recall anymore what the opening bid amount was, but it was fairly low. There wasn't much activity, though, so I determined that it would be mine, deciding what my maximum price would be, then waiting until the last 10 seconds remaining of the auction before placing my bid. I won it for $219.50! I was astounded. I can't tell you how many times I've lost out in the last few seconds of an auction, being seriously outbid by a large amount by somebody who wanted the item a lot more than I did. But two hundred nineteen bucks? Man, was I ever stoked. The only thing I can think of for it not getting any more interest than it did was that it was missing the case and filters. Big deal, I said to myself. I have a nice glass case I keep my Tamrons in, so its case is not all that necessary. And I have camera bags large enough to hold it when it comes time to pack it somewhere. And I'm not even all that sure it came with filters anyway.

So, yeah, if you're patient, it is indeed possible to pick up one of these beasties for a good price.
Site Supporter

Registered: June, 2008
Location: Florida Hill Country
Posts: 17,377
Review Date: February 14, 2015 Recommended | Price: None indicated | Rating: 8 

Pros: Well built optically and mechanically
Cons: huge
Sharpness: 9    Aberrations: 8    Bokeh: 8    Handling: 7    Value: 7    Camera Used: K20d   

This is a good lens, but it requires a very good tripod and should be mounted directly to the tripod because it is too heavy to mount it via the camera. This a good lens for blind work for wildlife or stationary work due to its size. It is incredibly sharp. I find it better at 500mm than my Takumar 500/4.5. Both require a tripod and have similar handling issues due to size and focus throw. This lens is a different design and optically superior to the 06A it replaced.
Site Supporter

Registered: January, 2007
Location: Toronto
Posts: 17,888

2 users found this helpful
Review Date: June 25, 2011 Recommended | Price: $350.00 | Rating: 8 

Pros: Minimum focus distance
Cons: front heavy on tripod
Sharpness: 10    Aberrations: 7    Bokeh: 8    Handling: 5    Value: 9   

Note that I have not rated this lens yet, but this is a work in progress.

Test shots with flash (otherwise hand held) are quite sharp when stopped down modestly or even wide open.

Focusing is a little slow with 350 degree focus throw, but that was not a surprise as I got to touch and feel this lens before purchasing it.

I have not yet tried it with a TC BUT i do note that the throat is large enough to accept the sigma APO teleconverters as well as the elements being recessed enough to take pentax rear converters meant for long lenses, so there are lots of options to take this well beyond 500mm with what are considered excellent teleconverters.

While my copy has seen some use, and the case is beat up, it came with all the accessories including the TC, front and rear filters, 2 nikon mounts, and a pentax KA mount all for the price shown.

Considering other prices listed here, I got a good deal.

First Edit

The lens is very difficult to use due to the imbalance of the lens on the tripod mount. A gimbal mount makes this much simpler but it requires a 4 inch lens plate to achieve balance (3rd edit). Also the lens is much better balanced (with no adaptor plates) with a teleconverter mounted. It should also be noted that as the length and CofG change with focal length, some attention is needed to reset the balance with each focal length. Setting the Cog F slightly below the pivot center of the gimbal head makes the lens a little more stable, and less sensitive to changes in CofG while zooming, and makes the tendancy of the lens to fall back to roughly level, as opposed to tipping forward or back, when you let go with no drag on the pivots

Using the lens when properly supported is a pleasure, and the close focus makes for some interesting shots.

Focus throw is not a hindrance unless you are constantly moving from near to far supjects. Then it is a bit slow, but not overly so.

THe biggest negative so far is that the adaptall II mount cannot go to F5.6 for maximum aperture, but only F4. THis means for P-TTL flash exposure is off. I intend to paint over the contact patches to have the lens report true aperture.(3rd edit) painting over the correct spot to make the lens read F5.6 (see mark roberts k mount lens contact data) makes flash exposure perfect

more to follow when it gets light and I can take some shots

Second edit

Focusing manually with the K7 and stock screen is simple and quick/accurate due largely to the narrow DOF and the long focus throw, the subject seems to snap into focus.

I have posted a link to some photos, which demonstrate what the lens can do, both good and bad.

biggest issues are lack of sharpness due to vibration (common with any lens of htis length) and PF when shooting into bright backgrounds. (third edit ) i have noticed some internal reflection off the iris, with bright subjects dead center, but not consistently See images in the sample archive

third edit
A few additional points to note, although I have posted any shots, you can achieve in daylight focus when using the SMC-F 1.7x AF converter, and can get focus confirmation using the sigma APO 1.4x converter although obviously no AF
Site Supporter

Registered: December, 2009
Posts: 45
Review Date: April 21, 2010 Recommended | Price: $450.00 | Rating: 8 

Pros: good sharpness for the range
Cons: heavy and with an unusual balance point

I've owned 2 of these lenses. The first got me an image that was used by a wildlife refuge for one of their brochures. It is an unusual lens. It is a more traditional optical formula with no ED or LD elements so it had to be made longer to get good optical correction. Still the results are very good. Sharpness is excellent throughout most of the range and only drops a litttle at 500mm (but not too much). Better than all of it's contemporaries at that point. Some CA in the corners but not a lot. Biggest issue is the placement of the tripod ring due to the optical parameters. It is way too far in the back. Many users make a plate to be able to mount the lens and camera a little farther back. My 2nd one came with just such a plate from the previous owner. Can be handheld better than the 300/2.8 and 400/4. Best used on a monopod at the least. the first one worked well on my *ist D.
Kent Gittings
Senior Member

Registered: November, 2007
Location: Tennessee, USA
Posts: 110

1 user found this helpful
Review Date: March 3, 2010 Recommended | Price: $680.00 | Rating: 8 

Pros: Sharp above f/8. Solid performer w/nice bokeh.
Cons: Occasional CA when pressing my luck. WEIGHT!

I love quality of the images produced with this lens. I would use it more frequently if weight weren't such a factor. For me, a tripod is a must when using this one--even if the tripod was my husband as was the case when capturing this shot.

ETA: Images were shot with my original *istDS

I'll share an example of the CA as well. This shot was taken in lower Plaquemines Parish not far from the U.S. Coast Guard facility at Venice a couple of months before Katrina graced us with her presence.

Add Review of Tamron Adaptall-2 SP (31A) 200-500mm F5.6

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