The TTartisans 17mm is a wide-angle lens that perfect for still-lifes, close-ups, street, and travel photography. Weighted 248g only, It is a great tool that should be in every photographers’ kit bag. The wide-angle of view(81°) pair with the large f/1.8 aperture can easily handle different lighting conditions. Its optical system consists of 9 elements in 8 groups and has a 10-blade diaphragm that contributes to a smooth and pleasing bokeh quality. It has a minimum focus distance of 20cm and a 40.5mm filter thread.