Why Tamron Di lenses are a perfect solution to many of your photo needs

John Swainston, April 2010

Since 2004, Tamron has extensively updated a significant number of its award-winning designs, adding the new designation Di – Digitally Integrated. The seven Di lenses currently available range from the SP AF28-75mm f/2.8 XR Di LD Aspherical to the SP AF200-500mm f/5-6.3 Di super-telephoto zoom.

A digital camera sensor, whether CCD or CMOS, possesses different reflective characteristics to those of film. This in turn affects internal reflections in a lens, as well as how the camera's light meter works. To avoid reflections which adversely affect image quality through ghosting or flare, Tamron has developed all-new coatings and lens treatments that minimise such effects. This often considerably improves lens contrast, a key factor in the "bite" of a photograph. So a Tamron Di-series lens provides superior image quality to many older lenses, especially in wide-angle.

A Tamron Di lens is perfect for photo enthusiasts who still use film, or the growing number of “full-frame” digital SLRs. By retaining a full image circle capable of covering the 24x36mm of a film negative or a sensor of equivalent dimensions, these lenses are suitable for film cameras and digital SLR cameras from the same makers. For example, Canon-mount Tamron Di lenses can be used on any of their current DSLRs, as well as all EOS film cameras.

In the case of 18x24mm-sensor DSLRs (with either 1.5x or 1.6x magnification of the lens’ nominal focal length), a Tamron Di lens, with its large image circle, uses just the central 2/3 of the lens. It provides sharper image detail in the corners on digital SLRs than a lens originally offered in film-only days, which used the whole lens surface area. The lens is also perfectly suited to film SLRs going back many years.

By contrast, a Di II lens from Tamron (for smaller-format APS sensor DSLRs) uses the smaller image circle to great advantage by optimising lens performance around the smaller image circle of the 1.5x magnification standard of Nikon, Sony and Pentax, or 1.6x of Canon, allowing for more compact lens design, also saving weight and bulk.

While such diversity of camera design approach continues, Tamron continues to provide for nearly all types of user. As yet, Tamron does not cater for 4/3 or Micro 4/3 accessory lenses. Given that the larger formats occupy more than 95% of the market, most users are well catered for. Tamron’s most recent development of VC technology (Vibration Compensation) certainly has lifted the bar, and is now available in lenses in both Di and Di II formats.

Happy picture-taking with Tamron!