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Tamron Adaptall-2 300mm f/5.6 (54B)

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8 39,528 Mon April 5, 2021
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88% of reviewers $93.17 8.00
Tamron Adaptall-2 300mm f/5.6 (54B)

Tamron Adaptall-2 300mm f/5.6 (54B)
Tamron Adaptall-2 300mm f/5.6 (54B)

One of the best MF 300mm/f5.6's - if not the best around.
Pic 2 shows the lens fitted with a, slightly modded to reduce the ID to ~62mm, 65mm ID tripod mount ring (chinese clone). There is an original tamron ring that crops up on the s/h market that fits similarly.

"A very good fixed focal length lens with excellent macro capabilities. Lens continuously focuses from infinity to 1:3.3 macro and features a built-in lens hood. Most importantly, this lens features a special "spherical aberration compensator group" to remove the focus group's spherical aberration and field curvature when close focusing. A similar optical group is also found in several other SP telephoto lenses which Tamron produced during the 1980s. This lens is worth the price if you need a lens for macro work yet need considerable working distance from the subject for personal safety or other reasons. This lens should have sold better in its day, but few photographers understood or appreciated the benefit of the spherical aberration compensator group used within this lens for close focus work. -

Focal Length (mm) 300
Aperture Maximum 5.6
Aperture Range 0
Field of View (24x36mm format) 8
optical construction (elements / groups) 6/5
Coatings BBAR Multi layer
Minimum focus distance (mm from film plane) 1400
magnification ratio 1:3.3
filter diameter (mm) 58
"length ( mm at infinity)" 163.5
maximum diameter (mm) 64.5
"weight (g)" 610
Hood built in.

The 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.

Accepts both 01F 2x TC and 014F 1.4x TC's. Note: TC's are reviewed in miscellaneous lenses - TC's.
Mount Type: Third-party (adapter required)
Price History:

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New Member

Registered: February, 2016
Posts: 3
Lens Review Date: April 5, 2021 I can recommend this lens: No | Price: $75.00 | Rating: 4 

Pros: Lightweight, minimum focussing distance
Cons: CAs, soft wide open
Sharpness: 5    Aberrations: 2    Bokeh: 6    Handling: 8    Value: 5    Camera Used: Canon eos 600d, Olympus em5   

Its promising specs and good reviews led me to get this tamron 54b 300/5.6. I have to say it ticks two nice boxes, those of light weight and close-up capability.
Sadly, all that was let down by its IQ, which I found quite poor. The main gripe: CAs wide open in highlights are terrible, unacceptable, IMO. They lessen as you stop it down, even half a stop makes a difference, but they are still present until at least f8 or f10, which renders this lens nearly useless for me. Aberrations are especially nasty at mid and close range. If the subject is in the shade, they are not a problem, but any sunlit scene is bound to be ruined.
Besides, you also have to close the aperture for acceptable sharpness, to at least f8. This defeats the weight advantage, because at slower speeds it is very difficult to handhold.
My Tair 300 3s blows it out of the water for resolution and minimal CAs. But it is so heavy...
I also have Tamron sp adaptall 60-300, and it might be slightly sharper, with less aberrations than the 54b, but nowhere near as good as the Tair.
On the upside, it can serve as a decent macro lens for butterflies, when and if purple fringing does not kick in.
Conclusion: for general use, even close-ups, many modern telezooms will outperform the 54b, with the added perks of autofocus and stabilization, and they can be even lighter.
If you are a Canon user, don't waste your time with vintage long tele lenses (unless you want to pay big money for higher end glass). Buy a cheap 55-250 and rest assured it will be much better in every respect, especially the latest STM version (I own both). I also shoot Olympus micro 4/3, and my 75-300 is another winner. I'm sure other brands have similar offerings.
IQ: Tair 3s>Tammy 60-300> Tammy 54b
Canon 55-250> or = Tair 3s
Canon 55-250 stm> Canon 55-250
Junior Member

Registered: January, 2013
Location: Texas
Posts: 32
Lens Review Date: May 8, 2020 I can recommend this lens: Yes | Price: $80.00 | Rating: 8 

Pros: Short minimum focus distance, Light, Well Built
Cons: Average sharpness, C.A.
Sharpness: 8    Aberrations: 6    Bokeh: 9    Handling: 10    Value: 10    Camera Used: Olympus Pen-F, Fuji X-T3   

This lens is superbly built (essentially metal), it has a very convenient short minimum focus distance, it is 'sharp enough', and it is light and thin.
Its two weaknesses are the physical length, not very convenient, and the chromatic aberration ('purple fringing') when the subject has high contrast, and the light source is behind. The branches of a tree, for example, with the sun behind. Or a roof top.
Site Supporter

Registered: February, 2017
Posts: 942
Lens Review Date: September 2, 2017 I can recommend this lens: Yes | Price: None indicated | Rating: 9 

Pros: value for money
Cons: needs tripod collar for best handling
Sharpness: 9    Aberrations: 9    Bokeh: 9    Handling: 8    Value: 10    Camera Used: K3   

I've had this lens a few months now, paying 60 complete with PK adaptor. Its typically well built, as many lenses were of this era, with good balance and smooth focusing and aperture ring. It has a built-in hood.
I bought it because of its close focus abilities so that I could capture images of insects at a comfortable distance.Its proved its worth in this respect over the summer with many fine pictures of bees, hover flies, damsel flies and butterflies. Using the manual setting on the K3, I limit the iso to 800 max and set the aperture to f8, and get excellent results.
It really needs a tripod collar and be used with a monopod or tripod for best quality. Fortunately I already had a Tamron collar that fitted. These are very rare. But you can get a slightly over-sized Canon compatible one and add a sleeve of old bike inner tube between the collar and lens barrel for the same result.
As to image quality I think its excellent. I have a 12mp crop of a damsel fly blown up to 16" X 12 " enlargement and its still dead sharp with beautiful colours and out of focus blur at f8.
In short excellent value for money, good build quality, excellent image quality. Highly recommended.
Site Supporter

Registered: November, 2012
Location: North Wales
Posts: 2,413
Lens Review Date: April 1, 2016 I can recommend this lens: Yes | Price: $90.00 | Rating: 8 

Pros: All round quality, compact size, close focus
Cons: Sharpness maybe a tad shy of "SP", fringing.
Sharpness: 8    Aberrations: 6    Bokeh: 9    Handling: 9    Value: 8    Camera Used: K5, NX20, lumix G1   

The Adaptall f5.6 300's have a particular USP for pentax users: there is no direct equivalent in the Pentax legacy lens lineup. The SMC-M and SMC-A 300*'s are much higher end high spec beasts: f4, larger, ~ twice the weight and several times the price on the occasions they crop up. The closest equivalents in price are the M42 takumars, again f4 (the 300mm f5.6 tak is the ultra rare "ultra achromat"). The SP 54B superceded the adaptall-1 CT300, which superceded the very first version which was derived directly from the earlier adaptamatic mount lens. 54B is readily distinguishable from the CT300 by its lined as opposed to crinkled rubber grip and "beercan" profile, the adaptamatic derived version 1 is significantly larger and has a built in tripod mount.

My first 54B was, and is, a bit of an old beater. However in spite of its dings and scratches, and slightly rattly focus, it performs just about as well as a LNIB one I acquired subsequently.
In my opinion it is probably the best vintage non-OEM 300mm f5.6 available, and I have tried quite a few. It's sharper, especially at f5.6, contrastier and warmer OtC than the adaptamatic and the earlier CT300. Stopped down though those two lenses catch up in terms of resolution. It's particular USP is its close focus, a point on which it leaves all those old generic preset/t-mount 300's for dead, and I have taken for example nice flower pics with this lens.
I do have a bit of critique of the 54B. For me the ~180deg focus throw is just a tad short (I particularly like the adaptamatic/adaptall version 1's handling and ~270deg throw) More significantly the 54B definitely has a propensity to strong purple fringing in certain circumstances. I could also remark on the lack of a tripod mount but that is easily remedied with a cheap 66mm TM from China (usually described as for Canon), used with a bit of packing or modded to fit. And finally I have to say that although its good, it's not in truth the sharpest, this is shown up by use with the 01F 2x TC, results from which for me are persistently disappointing, and also when I obtained a preset t-mount tamron 250mm f4.5 that was slightly, but definitively sharper, especially through f5.6, and had less fringing to boot!

One other question you might ask is: how does the 60-300mm 23A compare with this? I haven't done a definitive comparison, but I can suggest that overall it has similar resolution but a different character/rendering. 23A isn't in fact 300mm though - more like 285mm!

Price cited is typical auction (but can go up to ~ $150). At that price you should be happy, however much more than that and you should probably be considering a s/h DA/DAL 55-300mm, which is probably about as sharp and has AF of course. Overall 8 - 8.5/10.

1:1 pixel peep test crops of the castle (again), K5, f5.6, f8, f11 jpg from RAW default settings only LR3.

Note PF on the contrast boundary betwen the guys white t-shirt and jacket. Typical 54B! However it's only fair to point out this lens is in other respects good for control of CA - there is no purpling on the edges of the tower on the pics from which these crops have been taken, test pics of a sign with dark writing on a white background are true in colour not purpled, I don't tend to see fringing on eg horizon lines either. But I do see quite strong longitudinal CA off eg sunlit subjects like this.

Sample pics, developed from RAW in LR3, cropped:
Lumix G1.

Pentax K5

Samsung NX20

Crop (not quite full sized ~ 90%). F8

More pics:
300mm lens club #20600
300mm lens club #17252
New Member

Registered: December, 2012
Posts: 13
Lens Review Date: September 1, 2013 I can recommend this lens: Yes | Price: None indicated | Rating: 9 

Pros: lightweight, close focus, interchangeable mount

The only disadvantage is that the PK A adapter won't read correctly on a lens slower than f4.5. You can use it with the PK A adapter but in the viewfinder it will read as if the aperture is faster than it really is. I just keep a regular PK adapter on it that came with another adaptall lens I bought and stop it down to take a reading. It is lightweight and hand holdable but my copy came with a nice removable tripod mount that will also fit the 200mm adaptall f3.5. It focuses rather close for a 300mm and also works well with the 58mm Canon 500D achromatic closeup lens for macro type of shots. To me it is quite sharp and the colors are nice. Like all adaptall lenses it also works well with my Nikon using a N/ai adapter (minus image stabilization of course). I don't use it as much since I bought the Pentax DA 55-300mm zoom but the Pentax zoom won't focus as close. A faster 300mm prime would be heavier and a lot more expensive. The speed is not too bad with the K5 sensor. The adaptall 135mm, 200mm and 300mm primes all have the same look and diameter and all take 58mm filters. I have all three and I plan to keep them. They are all pretty decent and inexpensive. The other two work fine with PK A adapters. If you like the older manual focus primes I would recommend you look for a copy.
New Member

Registered: February, 2013
Posts: 2
Lens Review Date: February 17, 2013 I can recommend this lens: Yes | Price: $79.00 | Rating: 9 

Pros: sharp, light weight, very good bok
Cons: purple fringe in high contract
Sharpness: 9    Aberrations: 8    Bokeh: 10    Handling: 9    Value: 9   

It is one of the best lens I own(20 of them). It has very good IQ and light weight, so I can take to to wild places and shoot all day and will not hurt my arms. See pic.


Registered: June, 2010
Location: North Zealand, Denmark
Posts: 1,516
Lens Review Date: March 9, 2012 I can recommend this lens: Yes | Price: $110.00 | Rating: 9 

Pros: Close Focusing Capability, sharp, good habdling, low weight
Cons: Some CA wide open, not too fast

When I (finally) got my 54B at a reasonable price after several lost biddings, I got myself a lens that has been very much used, or should I say: Worn. This also implies focus creep and some loosenening of the rubber on the focus and aperture grips. The upside of this is that the original owner has obviously found it useful - and used it a lot. I have not let the state of wear of my particular copy degrade my rating of the lens as such.

Because it is an excellent lens in most respects. It isn't that fast, but on the other hand you get a very compact (for a 300mm lens) and easily portable lens. Handling and focusing is superb and Catch-in-Focus works very well with this lens.

It also works very well with Tamron teleconverters, and the lens' close focus capabilty is a real plus.

On the downside, I do see some chromatic abberations and a bit of softness when I use the lens at full aperture. As said, my lens is rather worn, but cosidering its general very good sharpness, I don't think my copy is in much need for collimation.

Overall a very good buy.

Veteran Member

Registered: April, 2008
Location: USA
Posts: 1,901
Lens Review Date: October 19, 2010 I can recommend this lens: Yes | Price: $125.00 | Rating: 8 

Pros: Lightweight, close- focus ability, interchangeable mount
Cons: Slow f-stop

This was one of the first Tamron Adaptall lenses I tried out. The first thing I thought when I saw it was "Wow, this thing is light for a 300mm lens".
The next thing I checked out was its close-focus abilitly. " Cool, not bad. "

I don't have any photos to put up that I took with this lens but what I remember was it not a bad little preformer for its price range. It's actually pretty decent. The build is nice and comes with the built in hood. For a con I put a slow f-stop but with todays cameras and high ISO ablities it doesn't really matter much like it use to.

So, for someone that doesn't have a pocket full of money and looking for a len in the 300mm range I would definately recommend trying this one out. Especially if you already have the Adaptall P/KA adapter. It doubles as a 300mm close-focus lens and that is
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