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View Full Version : Legacy Lenses Tamron 35-70mm f3.5



snaarman
02-17-2008, 09:52 AM
This is the latest in a series of alien lenses I have converted and tried on my E-400.

Descripton:
Tamron made two ranges of lenses, the SP "pro" grade and Standard grade. This lens (a Tamron 17A) from the standard range has a fixed open aperture across the range. At a minimum of 3 inches long its quite compact on the camera, however it extends to 4.5 inches at the wide end or in close focus mode.

Cost:
and cost me about 48 dollars on ebay (including a Minolta camera, a 2x teleconverter and a flash unit...) Discarding all the other stuff, I set about converting my Konica/Adaptall mount for 4/3ds. This turns out to be more complex that my previous Konica conversions(*) but after some fine adjustments I have the lens fitted and operational on the camera.

In use:
The lens feels very well made, smooth and pleasing to use. It has a two ring action, one ring for focus and one for zoom (well almost). In fact the zoom and focus rings are interconnected by some fantastic internal mechanics, so as you focus closer than 3 feet, the zoom ring automatically rotates backwards from 35mm towards 70mm. Its a smooth action and fascinating to watch!

The intention is to allow the lens to go seamlessly from view mode to macro mode simply by turning the focus ring (macro only operates at the 70mm end of the lens). This idea works well and I think the macro is a major feature of the lens, and it provides a field of view of less than 2 inches at max magnification.

The attached images show results at 35mm, 70mm and full macro magnification.

Conclusions - Pro:
Well made classic metal lens with nice smooth zoom and focus action.
Excellent close up/macro facility.
Very little distortion.
1/2 stop aperture clicks up to f16, full stop clicks to F32
Low cost general walk about lens.
Compact design, looks "right" on a small camera.
Good optical performance for a legacy zoom lens.

Concusions - Con:
Short zoom range. Probably not as sharp as a modern digital zuiko.
Modifying the Adaptall mount is a complex task. However, once you have done it, you have access to all the Tamron lenses!
Needs a lens hood to keep stray light off that exposed front element.
A strange WB effect: If you shoot auto WB, the image turns cooler at f8 and beyond. This doesn't happen in fixed WB and RAW modes. New one on me...
If it were a f2.8 design it would be even better, I find using the standard Katzeye screen to focus at f3.5 is tricky.

Hope this helps... :smile:

Pete
(*) Further thoughts. There is a better version of this lens (the SP 35-80mm) which is supposed to be excellent. It is longer and heavier however.

Other Konica mount lenses I have converted and tried include Hexanon 28mm f3.5 40mm f1.8, 50mm f1.8 and a Vivitar 28mm f2.0.

Here is a link to my lens results page http://www.snaar.co.uk/lenses/index.html

tspore
02-18-2008, 03:00 AM
Very nice looking kit.