I recently purchased the Sigma Art 35mm f1.4 DG HSM (Canon) and wanted to compare it to my friends Yongnuo’s 35mm f/2 lens and the results are surprising. I've also included the Canon f1.4 50mm (that I use most often) just to see the comparison.
The Yongnuo is about half the size of the Sigma Art and is super light (almost feather light) and seems to be made of all plastic. It does have a metal mounting ring with gold plated digital contacts and should help the lens mount from becoming damaged after prolonged usage. The Yongnuo 35mm f2.0 is a fixed focal lens that supports both full-frame and APS-C format camera systems. It features seven aperture blades and a minimum focusing distance of 0.25m; it can focus via a manual focus ring or the camera’s in-body autofocus system.
The sigma is significantly heavier and seems to be made with much studier materials. Personally I prefer a lighter lens (for my poor wrist) but I know that plastic lens could break easily and this is not something that you want to happen in the middle of a shoot. I had my camera fall off a chair recently and my Canon 50mm fell apart in 2 pieces! I had to buy a new lens but luckily I was finished the shoot.
The Yongnuo only goes down to f2.0 so in order to compare "apples to apples", I needed to compare the results of each image shot at f2.0 to make it fair. I photograph newborns at f1.8 often with my Canon 50mm and the Sigma has a gorgeous creamy bokeh at 1.8 and even more when you shoot wide open (the results at f1.4 are below).
As a newborn and family photographer, I would use the 35mm for newborns, however I didn't have a newborn for this test - it wasn't planned and I just wanted to do the comparison for myself... but then I thought other photographers might also be interested in the results too; especially when its almost a $1,000 difference!
I bought the Sigma on sale for $1,200 and the Yongnuo was only $139 on Amazon.
Here are the results: Overall I feel they are all pretty close - there IS a slight difference, but the Yongnuo 35mm is a great buy for the money!
I feel if you shot a full session and used both lens, you would not be able to tell the difference if shot at f2.0 or higher - possibly even f1.8 without inspecting every detail. If you want a 35mm and need to shoot lower than f2.0 I would recommend getting the Sigma Art 35mm or even the Canon 35mm...but I'll just stick with my Canon 50mm 1.4 when I need more depth of field. If you want to save money on a 35mm, then the Yonguo is great value! If you are looking for a brand name lens and price isn’t an issue, I would probably say to get the Canon 35mm or Nikon 35mm - that comes with image stabilization. Sigma is more of a mid-range price lens compared to the Nikon or Canon brands. I'm off to the store to return the Sigma and buy the Yongnuo!
If you're interested in purchasing the Yongnuo for Canon - Please use my affiliate link below :)