Pentax K-x, Tamron Adaptall-2 135mm f2.5, ISO 400, 1/90, f8
Tamron’s Adaptall-2 system was a brilliant idea. A nearly full system of high quality lenses with interchangeable, fully-couple mounts. It allowed you to invest in a selection of lenses which were not tied to any particular system. And the selection of lenses was excellent, with primes from 17mm to 500mm and zooms covering 24mm to 500mm along with a trio of teleconverters and a single 45mm extension tube. Lenses were split into two lines, the SP professional-grade lenses and the regular lens line. All of the SP lenses and many of the regular-grade lenses were excellent.
I own four Adaptall-2 primes and two zooms, and regularly use most of them. I currently have mounts for Contax/Yashica, Nikon F, Pentax K and KA, Minolta MD, Canon FD and Olympus OM systems.
The primes are:
SP 17mm f3.5 – A compact and excellent lens. I’ve got the second version without the integrated filters and do not have the dedicated hood. This lens is remarkably good, delivering high resolution in the centre, enough for even the high-density 4/3rds sensors and good performance out to the edges. It is somewhat flare-prone though, especially since I don’t have the hood.
28mm f2.5 – compact and reasonably close-focusing moderate wide. A solid but not exceptional performer, better than many 1st party 28’s (especially the Pentax SMC-M 28/2.8). Up to high-density sensors in the middle but average at the edges.
SP 90mm f2.5 Macro – Probably the best known Adaptall-2 lens, this legendary macro is known for its abilities as a portrait lens as well as for macro work. While it only goes to 1:2 natively , there is both an available 1:1 extension tube and the SP 2x converter as 1:1 solutions. Oddly, while the best of my 4 AD2 primes it’s also the least used. This is mostly because of its long focus throw, making it less desirable for walkabout use.
135mmm f2.5 – Relatively compact medium telephoto. This is one of the best 135’s I’ve used, easily outperforming the Nikkor and Pentax 135’s I’ve had in the past. Has a built-in hood and performs well from f2.5 down. It is labelled as a ‘Close Focus’ lens but with a minimum focus distance of 4′ or 1.2m, it isn’t actually close focusing.
Zoom lenses:
35-70mm f3.5-4.5 CF Macro – A compact and optically good little normal zoom. It doesn’t get much use though, due to poor handling (stiff zoom and focus rings being the main complaints) and my general zoom aversion, but the results have been excellent when I have used it. Close focus performance is remarkably good.
SP 28-80mm f3.5-4.2 CF Macro – Larger, heavier and wider ranged than the 35-70, it’s also a good performer and a nice option for a single lens to carry. As I just acquired it only time will tell how much use it gets.
Note that CF in the lens name refers to Continuous Focusing, unlike many zoom lenses of similar vintage the Tamron lenses with CF shift into their macro range automatically rather than requiring you to engage a macro mode. As with most zooms, ‘Macro’ means 1:5 through 1:2 magnification.
