The Sigma 24-105mm f4 OS Art lens could be the only lens you need for a full-frame camera. It’s slightly longer telephoto reach compared to the professional 24-70mm lenses is useful and can save carrying an extra telephoto lens. f4 isn’t ideal, but the optical stabilisation and high ISO capabilities of modern cameras largely makes up for this. It isn’t weather-sealed. It is big and heavy. It is good value, and a recommended buy as a lens to leave on the camera most of the time.Prime vs Zoom lens
Prime lenses (which can’t zoom) are great until you need to get a shot and you don’t have time to change lenses (assuming you even have the one you need). Most professionals don’t rely on a fancy 200mm f2 lens or even a 50mm f1.4; they use a general purpose zoom lens most of the time.What’s the best lens for …?
As photographers, we love the slightly wide-angle to slightly telephoto 24-70mm and slightly telephoto to longer telephoto 70-200mm lens combination. Occasionally, a wider lens like the 14-24mm will join the team, with a large-aperture prime lens added for low light/ shallow depth-of-field photos. Those four lenses are really all the vast majority of photographers will ever need. In fact, just the 24-70mm lens will be fine for most people.Is a Superzoom lens any good?
A super-zoom lens covers from wide-angle to long telephoto like a 18-300mm lens. Are they good lenses? Yes, because they are very versatile. No, because they make too many sacrifices. The Sigma has a 4.4x zoom range; I’ve never heard a professional compare a lens with this #x figure.The Canon/Sigma 24-105mm f4 lens
70mm is okay for a portrait, but 105mm is better. The Canon and Sigma lenses zoom in slightly more than the standard 24-70mm lens, which is often very useful. The Canon lens isn’t as sharp as the Sigma lens, but is weather-sealed. There are also lots of used Canon 24-105mm lenses available so if you can get one significantly cheaper (they’re already cheaper new) than the Sigma 24-105mm lens, it’s a good deal. Otherwise, because the Sigma is a little better at everything else, it is preferred.Vs. the Nikon 24-120mm lens
Nikon has a slightly longer zoom lens. However. the extra 15mm hardly makes a difference so isn’t a big factor in comparing the two lenses. The Nikon lens is more expensive, but it isn’t as sharp. It is lighter and uses 77mm filters compared to the heavy Sigma with 82mm filters; the Sigma feels sturdier.Vs. the Nikon 24-85mm lens
This lens is included with cameras sometimes. It’s lighter, plastic-y and the image quality isn’t as good. But the Nikon can be found cheaply second-hand and may suffice.f2.8 vs. f4
The professional 24-70mm lenses traditionally have a maximum aperture of f2.8. This helps blur the background a little more and lets in more light which allows you to use a faster shutter speed; important when photographing action or in low-light conditions. f2.8 is preferable, though it can make the lenses bigger/heavier. The Sigma 24-105mm lens has [...]