Roger at LensRentals.com has completed his comparison of the Canon EF 24-105 f/4L IS and the Sigma 24-105 f/4 DG OS.
Lots of people ask us which lens to buy and we usually say get the one for the best price, which for the last few months has been the Canon variant. While the Sigma is a very good lens, it’s not head and shoulders above the Canon by most accounts, if at all.
“Sigma has made a very nice zoom here at a very good price. It’s obviously not going to create the stir that occurred with their 35mm f/1.4 or 18-35 f/1.8 lenses, but it’s a nice addition to their lineup.
Canon shooters who have a 24-105 f/4 IS have no reason to change based on optics as long as the promotional pricing remains in effect. The Sigma and Canon 24-105s are nearly identical. Similarly the Nikon 24-120 has been available on discount lately, so I don’t see a big motivation for Nikon shooters to change, either.
Of course, if the pricing changes I wouldn’t hesitate to buy the Sigma instead of the name brands. If nothing else, I think the presence of the Sigma will keep Canon and Nikon prices reasonable.
I expect as this lens is released in other mounts it will be quite popular. There’s a reason Canon has sold about 3 gazillion 24-105s. It’s a very good lens with a very useful range. The Sigma will be available for Sony shooters next month and may be the best option in that mount.” Read the full review
Canon EF 24-105 f/4L IS $682 | Sigma 24-105 f/4 DG OS $899