Tamron 28A SP 28-135mm f/4-4.5

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

I picked up this lens last week for a pittance: $29 including shipping. It came with a Nikon adaptall-2 mount, which often sells for close to that price. So it was almost like buying the mount and getting the lens for free.

I was intrigued about it because of its zoom range. 28-135mm is a very useful range, encompassing the most popular wide angle settings and all of the most poppular portrait focal lengths. We're talking full frame or 35mm here, obviously.

This isn't a small lens, nor is it light. It's probably about a kilo in weight, with a 67mm front element. The 28A is a push-pull model. Mine shows some zoom collar slip, but to me this is no big deal. I'm used to it. It has a macro mode, getting down to only 1:4. So it's really more like a close-focusing mode, more than a true macro. Macro is engaged by depressing a button and then rotating the lens's barrel.

Some sample shots. They've been downsized to 1600 ppi. Followed by 100% crops. I used a NEX 7 for the following imiages. ISO 100.

The out-of-focus areas are blurred nicely at these close settings, giving pleasing bokeh.

marcusBMG · Joined: 07 Dec 2012 Posts: 1318 Location: Conwy N Wales

You got a bargain there Michael. The SP 28A was a premium lens, RRP a lot more than the similar 35-135mm 40A. I rate it pretty highly. It's a lot better than the 40A (and the earlier 22A) for close focus - both 28A and 40A (but not 22A - extra focus rotation at 135mm only) achieve that by lens extension ie just like using an extension tube - but IMO that's not saying much. It really shows well at its mid ranges focus and zoom and up to 135mm where for me it can give 135mm primes a run for their money. 135mm f8, pentax K-r:

Lloydy · Expire: 2022-01-01

The 22A is no slouch, it's a lens I'm using more and more - because it's a damn good lens. But I agree with Marcus, the SP 28A is the better lens.
I'd love to do a back to back comparison, but my 28A broke within hours of me getting it. Sadly it jammed solid when a roller in the zoom mechanism came off and the lens locked solid. The lens would not come apart unless I could move the focus / zoom slide, and no amount of force would do it.

I took maybe 6 or 7 pictures with it, and I was very impressed. I shall get another one.

visualopsins · Expire: 2025-04-11

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

The original size is 6000 x 4000 pixels. Way too big of an image for display here. 1600 pixels on the wide axis will fill the screen nicely with most modern hi-rez screens. To "downsize" I use my processing software, which reduces the image size to a specified level.

Marcus, thanks for including the seagull photo. The definition in the feathers is excellent.

visualopsins · Expire: 2025-04-11

Thanks...it was the "ppi" that threw me off..that should be "px".

cooltouch · Joined: 15 Jan 2009 Posts: 9096 Location: Houston, Texas

Yep. My bad.

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

Recently I got a second sample of the Tamron SP 4-4.5/28-135mm (28A) lens. The first sample was pretty heavily used, and I somehow wasn't sure whether the complicated zooming mechanism was worn out (or not). The second sample looks & feels like new, and therefore I'm more confident now to publish some test results (all at infinity / 24MP FF).

I have run these tests with a specifically manufactured M42=>Sony E adapter with tolerances of <10 um (adapter length, adapter "tilting").

First at f=28mm - below 100% crops from the corners of the 24 MP Sony A7II:

These crops (600x400px) represent the outermost 10% (linear) of the image. It's obvious that 90% of the image area are pretty sharp even wide open. At f11, more or less the entire image is well resolved, but some lateral CAs remain. If we convert the RAW data via PS, removing the CAs and sharpening the image at "50" and "1 px radius", the image looks really clean and crisp (100% crop from corner & midfield):

Distortion at f=28mm (!) is surprisingly well corrected (at 135mm things look different). Keeping distortion low at the wide end probably is a wise decision since at f=135mm usually portraits and reportage photos will be more important (and distortion less cumbersome).

Finally vignetting at f=28mm - pretty well corrected too (left at f4, right at f11):

S

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

At f=50mm and wide open the lens has a somwhat lower contrast, but a rather good resolution over most of the image. Stopping down to f11 gives nearly impeccable results: lots of detail even in extreme corners, good contrast, no CAs at all. Pretty impressive and comparable to e. g. the Minolta AF 4-4.5/28-135mm or the Zeiss ZA 2.8/24-70mm:

Converting the RAWs with PS doesn't give much additional detail, but it shows how good the lens really is at around 50-80mm:

Distortion now becomes more visible (pincushion), but isn't yet as disturbing as at f=120 ... 135mm. Vignetting still isn't really a problem (f4 on the left, f11 on the right):

The SP 28-135mm really is shining here at f=50mm ...!

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

At f=80mm things look nearly as good as at f=50mm, at least when the lens is stopped down to f11:

Wide open, the resolution is somewhat reduced (a tendency that will become quite obvious at f=120 ... 135mm), but stopped down we still haven an excellent image with no visible CAs at all. Pincushion distortion increases again, now being visible in critical (architecture) shots. Nevertheless the overall image quality still is very good.

Vignetting now is apparent at f4.5 (left), but still negligeable at f11 (right):

S

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

Finally at f=135mm:

Wide open (at f4.5) the image center has very good detail resolution and a very good contrast, too. Off-axis however the resolution drops pretty fast (while the contrast remains), and lateral CAs are are rather visible. Stopping down to f11 improves the situation, but the crispness and clarity of images in the 35mm ... 80mm range are missing even at f11.

Using PS fro RAW data conversion improves the f11 image quite a bit, but it never becomes really convincing:

Distortion too now is "too much", as seen here in this architectural snapshot:

It now certainly will be interesting too see how the three (four) famous 28-135mm from the 1980-1985 time frame compare:

Minolta AF 4-4.5/28-135mm
Konica AR 4-4.6/28-135mm
Tokina AT-X 4-4.6/28-135mm
Tamron SP 4-4.5/28-135mm

Such a test will require a bit more time, and more stable lighting conditions.

For time being, I am pretty impressed with the performance of the lens in the 28-80mm range (and probably also around f=100mm). Stopped down to f11 it's perfectly useable especially for landscapes on 24 MP FF, but architecture shots will require some work in post processing (mainly CA removal at the short end and distortion correction from f=50mm upwards). There's another caveat: Due to the complicated zoom mechanism, wear-and-tear might result in lower performance than seen here.

I hope this is useful to some.

S

D1N0 · Joined: 07 Aug 2012 Posts: 2537

Good for portraits too Wink

135mm wide open

Grimpy by The lens profile, on Flickr

Or city 28mm probably F8 or 11

A situation in the Oude Boteringestraat by The lens profile, on Flickr

Macro @28mm

Daisy in the grass by The lens profile, on Flickr

lumens pixel · Expire: 2021-06-25

Thank you. My findings are quite similar. This is why I have favoured the 27A which limits its range to 28/80 and good results throughout the range. Less weight and a closer minimum focus distance. The results of the 28A above 100 mm are not engaging.

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

Doc Sharptail · Joined: 23 Nov 2020 Posts: 1216 Location: Winnipeg Canada

Thanks for adding this test. Nice to see a "new" test subject too Wink

Stephan!

I normally avoid lenses of extended zoom focal range.
The early ones that I tried were pretty disappointing. Some reviewers of these lens types back in the day were far from impressed.
The Tamron shown by the O/P of this thread looks to be an improvement over what I have seen in the earlier lenses.
I'm still not entirely convinced enough to look for one yet.

I do have a couple of nikkor zooms that don't quite make the focal ranges exhibited here: A/I-s 35-105, and A/I-s 28-85.
I think these were among the last m/f lenses that nikon made, but still have a lot of reading up to do on them. Both are capable of producing usable images, albeit under favourable conditions. I still do not use them much with my propensity for the more stable aperture speeds of primes, but I'm a bit of a dinosaur hold-out when it comes to such matters.

-D.S.

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

lumens pixel · Expire: 2021-06-25

Ultrapix · Joined: 06 Jan 2012 Posts: 576 Location: Italy

I own this lens, but frankly I find it uncomfortable to use because of the huge focus range at the shorter focal lengths, to make it virtually impossible to determine the point of greatest sharpness. In contrast, the color rendition and some vignetting at 135 mm I like very much for portrait or fashion shots

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

Ultrapix · Joined: 06 Jan 2012 Posts: 576 Location: Italy

stevemark · Joined: 29 Apr 2011 Posts: 4087 Location: Switzerland

Doc Sharptail · Joined: 23 Nov 2020 Posts: 1216 Location: Winnipeg Canada

I recently bought a copy of this lens that has seen a bit of use.
It suffers from an expanded rubber grip on the focusing collar. I will have to find one that is tight enough to fit.
The glass is clear with no haze or fungus. There is a bit of internal dust on the elements~ not really surprising on a lens this old.
The information on it on the adaptall-2 site seems to be fairly consistent with what I'm experiencing.

Fall-off is a bit steep at the 135 end.
I'm not sure how to label the slight distortion at the 28mm end- it seems to be both pincushion and barrel distortion, depending on where you are in the frame.
Sharpness is very good for a zoom from this period, up to about 85-90mm, then the fall-off starts.

The macro/close focus function appears to work fairly well on my copy, giving some comfortable shooting distances.

It is an interesting lens, if not a little big and heavy.
Performance-wise, for all the bulk and weight, the nikkor 28-85mm A/I-s is a much better fit in my bag, with slightly better I/Q at the 28mm end.

I still have to get out into some decent daylight at low ISO's to give it a fair test.
I think it's a lens I could learn to like, if I'm willing to put the time and effort into learning it's strength zones.

-D.S.

Doc Sharptail · Joined: 23 Nov 2020 Posts: 1216 Location: Winnipeg Canada

Some sample images:
All are un-manipulated except for re-size.

At 28mm and f8.
Slightly flat contrast here, but nothing major.
Color leans a bit more yellow than actual, but it is very slight.
Image center is very sharp for a wide zoom.
There is a bit of fall off towards the edges even at f8, but I have to "peep" considerably to find it.

At about the 50mm position here, and f8 again. I like this rendering a lot. Lens actually shows the weak side-lighting, which I was a bit surprised to see.

A bit over a 100% crop of image center.

At the max 135mm position. Fall-off is quite evident here at f8. Edges and corners are actually pretty blurred.

100% crop of image center. Not bad, but no where near the equal of the same shot with a prime 135 at f8.

At 135mm with the macro lug engaged to the stop. f8 and the D-810's built in flash as a fill light. Shadow cast by the lens is visible on the lower petals. Lens has a tendency to glow a bit on white subjects without the fill light.

It gets a bit curvy at 28mm with the lens front pointed slightly downwards. f8 again. The ground in this scene is actually a lot flatter than what is shown here.

Definitely an interesting lens- a bit better than I was expecting at the wide end, and decent at the mid part of the focal length range. I think I am keeping this one for it's rendering qualities.

-D.S.