Tamron is rumored to announce a new 17-50mm f/4 full-frame lens in the next few days. Tamron has already filed a patent for such a lens: Tamron 17-50mm f/4 VC Patent Found Via Camerainsider Related posts: Tamron announces the development of a new 70-180mm f/2.8 Di III VC VXD G2 lens for Sony E-mount