Sigma 870954 2.0x Teleconverter TC-2001 Canon

The Sigma 2.0x Teleconverter TC-2001 for Canon is a compact optical accessory that doubles the effective focal length of compatible telephoto lenses, turning a 150-600mm zoom into a 300-1200mm powerhouse or a 300mm prime into a 600mm super-telephoto. For photographers who need extreme reach — whether tracking birds in flight, capturing distant athletes, or photographing aircraft — the TC-2001 provides that capability without the size, weight, or expense of a dedicated super-telephoto lens. The teleconverter maintains full electronic communication with the camera body, preserving autofocus functionality, metering accuracy, and EXIF data recording.

As with any 2x teleconverter, the TC-2001 reduces the maximum aperture by two stops, which is an inherent trade-off of the doubled magnification. This means that optimal results are achieved with fast telephoto lenses — ideally f/2.8 or faster — where the resulting f/5.6 maximum aperture still allows reliable autofocus on most camera bodies. The converter is engineered for use with Sigma's Global Vision telephoto lenses, and Sigma maintains a published compatibility list to ensure users get the best optical and electronic performance. Firmware updates through the Sigma USB Dock keep the TC-2001 current as new camera bodies and lenses are released, extending its useful lifespan well beyond the initial purchase.