Tamron's premium super-telephoto — the 150-600mm G2 without mount specified.
The Tamron SP 150-600mm f/5-6.3 Di VC USD G2, released in 2016, is the second-generation super-telephoto zoom addressing key shortcomings of the original G1: faster autofocus, improved CEVA (Combination of Elements and Vibration Compensation Algorithm) VC rated at 4 stops effective, moisture-resistant construction, and a Flex Zoom Lock mechanism. Di indicates full-frame coverage.
150–600mm zoom range, f/5-6.3 variable maximum aperture, 4-stop CEVA VC, USD (ultrasonic AF drive), moisture-resistant construction, Flex Zoom Lock, fluorine-coated front element, Nikon F mount.
The G2 makes meaningful improvements over the G1 in AF speed and tracking, critical for wildlife and sports photography. The 4-stop VC is effective even at 600mm. The Flex Zoom Lock allows the barrel to be secured at any focal length. Its main competition is the Sigma 150-600mm Sport and Contemporary versions.
Test VC function at all zoom positions and confirm AF tracking accuracy on moving subjects if possible. Inspect front element coating for cleaning marks. Check Flex Zoom Lock operates correctly. Confirm Nikon F mount contacts are clean. Weather-sealed construction benefits from regular cleaning of the seals.