The Sigma 55-200mm f/4-5.6 DC is a budget telephoto zoom designed for APS-C DSLRs, covering approximately 82.5-300mm equivalent on Canon crop bodies. It provides basic telephoto reach at the lowest possible cost.
Optical quality is basic — acceptable centre sharpness at mid-focal lengths but soft at the edges and at 200mm. No stabilisation, which makes handheld use at 200mm challenging. Autofocus is adequate but not fast. Build quality reflects the budget positioning.
Available in Canon EF-S and Nikon F DX mounts. 55mm filter thread. Very lightweight at approximately 310g. No weather sealing. DC designation means APS-C coverage only. Minimum focus distance approximately 110cm. Plastic construction.
Very cheap used — often under £20. Only worth considering as an absolute budget option. The Canon 55-250mm IS STM and Nikon 55-200mm VR are dramatically better with stabilisation. Check for smooth zoom action and clear optics on used copies.