Tamron AF 70-300mm f/4-5.6 Di LD Macro £130, $150
Another budget Option that doesn’t quite deliver
Similarities between this and the two Sigmas on test include a 0.5x macro facility that, in the Tamron, is available from 180-300mm. You need to use the closest focus distance of 95cm to hit 0.5x magnification.
All three lenses have zoom and focus scales printed on their control rings, but the Tamron lacks a magnification scale, which is found on the extending inner barrel of the Sigma lenses. Yet more similarities include a basic motor for autofocus, a lack of optical stabilisation, and the fact that the front element rotates during focusing. This makes it tricky to use filters like circular polarisers and grads.
Widest-aperture sharpness at 300mm is better than from Sigma’s cheaper 70-300mm lens, but not quite as good at short to medium zoom settings. In other respects, image quality is similar, although autofocus is slower. With its plastic rather than metal mounting plate, the Tamron is about 100g lighter than the Sigma lenses, but this arguably makes it less able to overcome camera-shake.