I was so unimpressed by the Nikon kit lens that came with my camera, I've always bought Tamron. The problem was it wasn't that sharp, and pictures were too dark. The Tamron lenses produced a brighter picture with no edits, and the sharpness is OK with SP Tamron, which is their professional range. The sharpness improved since I upgraded the camera from a D3100 to a D7500, which a superior sensor - and with the SP lenses, that produces a very nice result. I had no idea that Tamron lenses were made by Nikon and had always been told that Nikon were far superior. But I didn't like the prices and wondered if they were all as dark as my kit lens.