If you need to strengthen your arms, get one of these. A sharp lens with a surprising 9 aperture blades. Beautifully smooth focusing. The Tamron's colours are quite saturated, reminding me somewhat of a Pentacon 135mm f/2.8, but with a slightly more "modern" rendering, whatever that means. At f/8 it can play alongside any modern telephoto except it flares in a lovely rainbow way when shooting directly into the light and loses contrast in the way that these old lenses do. A little tweak of the RAW file and pictures look like they were taken with a modern telephoto lens. It's incredibly sharp at infinity, making it a superb choice as a telephoto landscape lens. A great heavy lump of metal and glass.