The Tamron 28-200mm f/3.8-5.6 Aspherical IF LD Super (Model 571D) optical build incorporated Tamron's unique, creative and high performance technology. The super zoom lens employs two Hybrid Aspherical and Low Dispersion (LD ) elements to allow a decrease in the number of lenses and increase design flexibility, while ensuring more effective aberration corrections. The lens employs Tamron's Triple-Cam internal zoom system and an engineered plastic which protects the complex structure from shocks and helps reduce the weight of the product. The lens sports 16 elements in 14 groups, 6-blade diaphragm, 2.62ft close focus distance and 72mm filter thread.