Disclaimer: You couldn’t be blamed for reading this article and concluding that I hate Sigma lenses. That couldn’t be further from the truth. The Sigma Art lineup of lenses were the most influential pieces of gear I’ve ever owned and I owe a lot of what I’ve created to Sigma’s lens engineers. But the lenses aren’t without fault and the biggest one, that I’ll talk about soon, is why I’m swapping.

Shot on a Canon 5D IV with a Sigma 35mm 1.4 Art

All the way back in 2013, the Sigma 35mm 1.4 Art was the first lens I ever purchased (outside of bundled kit lenses). I bought it to pair with my Canon 6D, finally plunging into the world of full frame digital cameras. The width and depth of this lens tell a story no other lens in my kit can match, even today. It has been a workhorse for me ever since I bought it. 95% of the photos you see here on my website were likely shot with this very lens.

Since then, I shot nearly exclusively on an arrangement of Sigma glass (I had some cheap Canon lenses but rarely used them). I’ve happily shot many weddings, maternity sessions, proposals, engagements… etc all on my beloved Sigma lineup.

However, recently I’ve been selling them and moving back over to Canon glass, with only my 35mm art remaining. The moment Canon announces a 35mm RF lens (to pair with my new Canon R6), I’ll be retiring this lens after nearly 8 years of service and move away from Sigma forever.

but why?

It all boils down to autofocus consistency. At first, I absolutely suffered focusing with my Canon 6D. Try as I might, I could never get my lenses to focus consistently, missing all kinds of critical shots. I always blamed the 6D’s inferior AF system (with it’s measly 11 AF points). I dreamed of the day I would buy a 5D and finally join the real professionals with their abundance of AF points.

And then, in 2016, I was finally able to afford my first REAL camera, the newly released 5D Mark IV and was ecstatic about finally solving my crappy autofocus issues. However, I noticed that, while the autofocus was easier to use, the camera would still miss regularly miss focus. Only the dual pixel autofocus using live view would focus properly, but I couldn’t be expected to never use my viewfinder!!! After months of diagnoses and calls with Canon, they ultimately blamed the Sigma lenses I was using.

Hah! There is no way my LENSES are the issue, silly Canon. They just do what they’re told, you know, by the CAMERA you made! Clearly all 61 autofocus points in my 5D are horribly faulty. But then…. a revelation.

I bought the Canon 70-200mm 2.8 IS USM II and everything changed. This lens NEVER missed. It was perfect, on both my 6D and my 5D IV. Oh my god… Canon was right. It was the Sigma lenses.

One at a time, I’ve replaced my Sigma lenses with Canon lenses and my autofocus issues are disappearing.

is it really that bad?

To prove my point once and for all, tonight I pointed my 5D IV at a magazine and attached my Sigma 35mm 1.4 Art (the lens has been updated with the latest firmware). I reset the lens focus all the way forward before each shot, letting the camera refocus, using the centermost single AF point using the One Shot method and the AF beam on my speed light.

Control Shot: Focused using Live View AF.

Here are 100% crops of the first 4 photos I shot. As you can see, it took 4 shots before the camera found focus. Yes, I know this wasn’t the most scientific test with completely controlled variables. But I shot something like 20 photos and few were even close to focused.

But let me now show you 4 more photos shot on my “famously unsharp” Canon 50mm 1.4 lens. The Canon lens was given the same treatment as my Sigma lens.

Shot 2: Missed focus because I accidentally moved the tripod. But still I must include it in the name of “2am photographer’s closet” science.

To be sure the blurry shot can be blamed on the tripod, I went back and shot 10 more images on the Canon 50mm and they were all sharp. And as you can see, while the Canon 50mm 1.4 is a soft mushy piece of garbage, it at least can focus properly.

So you may be asking, “is this just a simple AF microadjustment?.” Well yeah, if the lens missed focus the same way each time, that could solve the issue! But unfortunately, the Sigma lens will forward focus, back focus, nail focus… all the colors of the rainbow. So no, that won’t solve the issue. It does seem to grab focus a lot better the closer the subject is, but more than a couple meters away? Forget it…

so what’s the point of all this?

Well I feel like there could be other photographers out there shooting on Sigma glass who have no clue why their images aren’t sharp unless they focus with the live view.

Speaking of which, the sigma lens NEVER misses focus on live view for some reason. I am not sure why, but Sigma’s lenses and Canon’s traditional phase detect AF just don’t mix. But swap over to contrast/phase detect live view? No problem… oddly enough. It’s actually hilarious that I’m nearly done switching away from Sigma glass because I just purchased my first mirrorless camera (The Canon R6) and it has zero trouble focusing with my only remaining Sigma lens.

However, I don’t regret the switch. I no longer want to put my faith and money into third party glass because who knows what kind of random issues I may discover in the future? I will be a pure Canon fanboy from this day forward and I hope anyone out there considering the switch will take comfort in knowing they aren’t alone.

some housekeeping

Obviously, there will be people who disagree with me.

”my sigma lenses NEVER miss focus"

”you’re wasting money on Canon glass!”

”your experiment wasn’t really fair, you failed to consider ____”

Look…. yeah…. it wasn’t a perfect test. It was merely a demonstration of a problem I’ve had with multiple sigma lenses used on multiple Canon cameras. This is a decision I’m making for myself and I’m hoping that my insight might help guide other photographers who are on the fence. But if Sigma glass is working for you, then I’m not hating! Keep shooting and loving your Sigma glass!

But I’ll be swapping thank you very much.