Abbreviation: DI = "Digitally Integrated" (Tamron)

The abbreviation DI means "Digitally Integrated" and is seen on Tamron products.

Explanation from Tamron

Digitally Integrated Lenses for Top Imaging Performance

Di (Digitally Integrated Design) is a Tamron designation that applies to lenses that have been optimized for digital capture using advanced multi-coating techniques and optical designs that assure excellent image quality across the entire picture field. Because of these characteristics, Di lenses provide outstanding performance on cameras with full-frame and APS-C format sensors as well as on 35mm film.

See examples of effected products

Tamron AF 28-300mm f/3,5-6,3 XR Di
Tamron AF 28-300mm f/3,5-6,3 XR Di VC
Tamron SP 17-35mm f/2,8-4 Di

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