Lenses are designed for exclusive use on digital cameras with smaller-size imagers and inherit all of the benefits of the Di products. These lenses are not designed for 35mm film cameras and digital cameras with image sensors larger than 24mm x 16mm.At Tamron, quest has always been to make the ideal zoom lens. As a result of this ongoing challenge, Tamron has introduced the concept of the high-power zoom lens in the new AF18-200mm XR Di II for exclusive use with digital SLRs. Tamron's original development of proprietary core technologies such as Aspherical element production, Multiple Cam Mechanism and Integrated Focus Cam design lend to the creation of the world's lightest, most compact 11.1X zoom lens made for digital SLR cameras.The 18-200mm (28-300 when converted to 35mm) provides the digital photographer with the versatility of a true wide to ultra tele-zoom in an amazingly easy to use design.