Fstoppers Reviews the Canon 40mm f/2.8 Pancake Lens

When the Canon 40mm f/2.8 pancake lens was announced a couple weeks ago, Canon fans all over were squealing with joy- myself included. This tiny lens would be great for life on the go, had a brand new AF engine called the Stepping Motor (or STM), and looked to be extremely versatile. But does it live up to the expectations?

I had serious high hopes for this lens. It is small, lightweight, opens wide to f/2.8, and inexpensive at a budget-friendly $200. Add to that the promise of quiet, smooth auto focus with its brand new STM (stepping motor) focusing mechanism and the ability for full time auto focus, and I was so ready to love this lens.

Pros:

The Canon 40mm f/2.8 pancake excels in the lightweight and user-friendly category of Canon lenses. I can definitely confirm that the promise of great image quality from center to edge of lens is fulfilled. Sharpness is not only consistent, but can be downright beautiful (Note: Can be. More on that later). The aspherical element Canon included into the lens configuration gives the 40mm pancake fantastic sharpness and color balance. Even wide open, this lens is sharp from the center focus point all the way out to the corners of the frame.

On the left, the Canon T4i. On the right, the Canon 5D MKIII. Lens was sharp on both, so long as I stayed under f/10.

The lens has a sharpness sweet spot at about f/7.1. That said, from f/2.8 all the way through f/9, it is nicely sharp and more than acceptable. This is great news for those of you looking for a lens that is sharp wide open. I noticed no vignette at all on the crop sensor cameras (Canon T4i and 7D), but did notice a little vignette on the 5D at f/2.8 and f/3.2.

If used under the ideal set of circumstances, this lens excels.
But the world is rarely ideal (click for high res).

Cons:

The Canon 40mm f/2.8 pancake lens struggles with sharpness the further you close it down, has a noisy focus ring, and let me down time and again with slow and inaccurate focusing. Oh and the STM motor does not really work well in full time auto focus, which is a real bummer.

For those not reading the full product description, you might get excited about would be the first bullet point on the product’s highlights: “STM – Continuous Autofocus for Shooting Video.” Sweet! I mean, I don’t ever use auto focus when I’m shooting video because it looks like poop, but maybe this will change everything!

Nope.

Sadly, the promise of continuous auto focus is only fulfilled if you own a new Canon T4i. It is the only Canon body out there that supports the new focus engine to the fullest, and it’s the only one with which you can use full time auto focus.

“Newly developed STM technology for smooth and quiet continuous AF while shooting video.”

This is kind of true. It’s quieter on the T4i, but it’s not quiet at all on any other Canon body.

When not on the T4i or using manual focus on any body, the focus motor on this lens is loud. I mean really loud. I like to compare it to the sound the Millennium Falcon makes when its hyper drive motivator malfunctions in The Empire Strikes Back.

You don’t notice noisy focus rings all that often unless you are listening for it, or shooting alone in a quiet room. I probably wouldn’t care so much about this if Canon didn’t sing it as a major selling point of the product.

If you have a Canon T4i, you can put the nifty full time auto focus feature to use. Well, kind of nifty. It’s not 100% accurate all of the time. It does a decent job, but the tech in the body of the camera seems to outpace the abilities of the lens. While the body recognizes where focus points are set, and where faces are, the lens struggles to keep up. It often loses the subject, focuses on the background, or just seems to give up and stop focusing altogether. Sometimes, if it can’t recognize a subject, it will focus and refocus rapidly, desperately trying to figure out what to dial in on, which results in jumpy, unusable footage.

Bummer, but not the end of the world, right? It still has all those other features that make this thing easily worth the $200, right? Right?

Well, no. Not really.

I mentioned earlier that the sharpness was consistent and “could be downright beautiful.” At certain apertures, the other side of “could be” rears its ugly head. I was shocked at how bad images looked when I shot at anything past f/9. This lens has a very steep falloff in sharpness between f/9 and f/10. It is a little worse on the edges, but that same consistency that I was initially impressed with has carried through when the quality of the image worsened. By the time I got to f/16, I was seeing crummy, blurry, muddy crap. F/18 through f/22 are nigh unusable.

It goes from good, to great, to crap (click for high res).

The nail in the coffin for me was the aforementioned slow auto focus. It’s not terrible on the T4i, and might be manageable after getting used to it. However, it was extremely frustrating on the 5D. I like to use auto focus when I’m in the studio shooting portraits (which I only did with this particular lens for the sake of testing) because I would rather focus on working with my model than determining if my image is sharp. This is, of course, a personal preference. But if I’ve got the model in just the right pose, but she had to lean an inch forward to get that perfect look, I don’t want to have to worry about checking if my image is sharp. I just want to grab that image before it disappears. My eyes aren’t perfect, so I like to leave those situations up to the camera.

If the 40mm pancake it is not on the T4i, the focus is slow, sloppy, and irritating. Often times, even if I have the focus perfect, as I press my finger down to capture the image the auto focus will change its mind and try and refocus. This can take anywhere between three and five seconds each time. After five or six instances of this happening, I just shut the auto focus off so I could finish my session in peace.

The slow auto focus coupled with the normal focal length doesn’t really make this an ideal studio portrait lens. I’ll stick with the EF 85mm f/1.8 or my Tokina 35mm f/2.8 macro.

The Verdict:

So should you get this lens? Well that depends. If you have a Canon body already and it is not a T4i, I can’t recommend it. It has too many glaring issues. I know the $200 price tag is tempting, but the lens just is not worth it. The slow and noisy auto focus, disdainfully blurry images past f/9, and the fact that you can’t take advantage of the full time auto focus makes this a pretty useless lens. Save your money and put it towards a lens that costs a bit more (like the 85mm f/1.8).

If you do have a T4i or are planning to get one, this might actually be an ok purchase. It’s not expensive, keeps the whole DSLR package small, and is lightweight. If you’re planning on doing some backpacking or travel, the T4i/40mm combo is a darn good alternative to a mirrorless camera. Since Canon does not yet have a mirrorless option, this is a good solution for those of you who don’t want two different sets of lenses cluttering up your home office. The T4i/pancake combo will be good for general-purpose landscape and street photography (the latter especially since it’s so small and inconspicuous). Just don’t plan to stop it down past f/9.

You can pick up the Canon 40mm f/2.8 Pancake (if you really want one) from B&H Photo.
Video shot on a Canon 7D and Canon 60D with a 24-105mm f/4 L and the EF 85mm f/1.8 (I highly recommend both camera bodies and both lenses). Lens close up b-roll was shot with my Tokina 35mm f/2.8 macro.

Canon 5d and T4i rented from BorrowLenses.com