Sigma APO 70-300mm f/4-5.6 DG Macro £150, $155

The ‘upmarket’ APO version of the Sigma 70-300mm is still very reasonably priced

Although it ‘only’ costs £150/$155, the APO (Apochromatic) version of the Sigma 70-300mm is 50 per cent dearer than the basic edition of the lens in the UK. There’s not such a big difference in prices in the USA. So what do you get for the extra money? The main advantage is that whereas the basic edition features a single SLD (Special Low Dispersion) element, the APO lens has three. The intention is that chromatic aberrations are more effectively eliminated, so you’ll see less colour fringing in images taken with this lens. That’s the theory.

Build quality feels identical in the two Sigma lenses, they have the same autofocus system based on an electric motor, and an identical 0.5x macro facility that’s available in the 200-300mm section of the zoom range. The only other notable difference between the two lenses is that the APO version comes with a padded carrying case, whereas the cheaper edition has none.

Performance

There’s no increase in contrast in low light, compared with Sigma’s cheaper 70-300mm lens. On the plus side, the extra SLD elements really do reduce colour fringing, but only towards the extreme ends of the zoom range. Sharpness is marginally better at long zoom settings.