I took two lenses with me on a recent portrait shoot: the Canon EF 85mm f1.8 and Canon EF 40mm f2.8 pancake lenses. I wanted to compare the aesthetics of each lens for portraits, and the results were interesting enough to show to you here.

First, let’s take a brief look at these two lenses:

Canon EF 85mm f1.8

The 85mm is a short telephoto lens. On a full-frame camera it’s the ideal focal length for taking photos of people, which is one of the reasons why 85mm lenses are often called portrait lenses. It’s great to work with because it’s long enough to take flattering head shots without any of the distortion associated with shorter focal lengths, but it’s short enough so you don’t have to get too far away from your model. As connecting and building a rapport are an essential part of any portrait shoot, it is helpful to be close enough to talk without shouting.

Another benefit of this lens is the wide maximum aperture of f1.8. I tend to shoot at f2.8, which is a kind of sweet spot that gives excellent image quality and shallow depth-of-field. Occasionally I switch to f1.8. The image quality drops off a little (the widest aperture setting of any lens always gives the worst result in terms of image quality) and there is more vignetting but these are not necessarily bad things for portraits. Sharpness isn’t everything, and there is a subtle dreamlike quality to images taken at f1.8 on this lens.

The biggest issue at f1.8 is focusing. The depth-of-field is so narrow that focusing has to be spot on (you can learn more about that here). The result when you nail it is beautiful bokeh.

The 85mm lens is a popular lens for all these reasons. Canon have two current versions, Sony have two, and Nikon really go for it with four (including a macro and a perspective control lens).

If you own an APS-C camera then a 50mm prime lens effectively replaces the 85mm lens, retaining all the benefits. An 85mm lens on an APS-C camera may push you too far away from the model when taking full-length portraits, making it harder to communicate.

Canon EF 40mm f2.8

Released last year, the 40mm pancake lens is a beautiful piece of kit. It has a slightly schizophrenic personality, working as a moderate wide-angle focal length on a full-frame camera, or the equivalent of a short telephoto on an APS-C camera. The maximum aperture isn’t as wide as an 85mm or 50mm prime, but the trade-off is that the lens is tiny, making it easy to carry around. My camera feels very different in the hand with this lens on as the centre of gravity is much further back. It’s easy to hold still and a pleasure to work with.

Pancake lenses are more common with Micro four-thirds and mirrorless cameras than SLRs. As far as I know no other SLR manufacturer makes a pancake lens. The closest you’ll get to this lens with other camera brands are either a 35mm or 50mm prime. Voigtlander make a manual focus 40mm lens for Canon, Nikon and Leica mounts.

If you own an APS-C camera then a 24mm lens will give you a similar perspective.

Comparing portrait lenses

Let’s look at how the lenses compare for portraits. Here’s the first example:

The top portrait was taken with the 40mm pancake lens. I deliberately moved in close to show the distortion created by this focal length. Used carefully, you can get away with it, and the portrait appears much more three-dimensional than the one taken with the 85mm lens.

But the best way to use the 40mm lens for close-up portraits like this seems to be to back up a little and keep the model’s face near the centre (distortion is greater towards the edge of the frame with wide-angle lenses). The opening photo is a good example, here it is again:

In terms of distortion you can’t go wrong with the 85mm lens. You won’t see any no matter how close you get, making it a safe option for portraits. The 40mm is more adventurous, but can go wrong.

You can also see the result of using the 85mm lens at f1.8 in the bottom portrait. The background is beautiful!

Here’s the next example, this time with full-length portraits:

At first glance there is little to choose between the two photos. But look closely – the portrait taken with the 85mm lens has a much flatter perspective. My model is standing at the corner of a stone block (I have no idea what it is for or why it was there) and you get a better idea of the shape of the block in the photo taken with the 40mm lens. The photo taken with the 40mm lens also includes slightly more of the background, and the background is slightly sharper.

Also note the white square painted on the cliff in the background. It appears larger and closer to the model in the photo taken with the 85mm lens. That’s another difference in perspective between the two lenses – the short telephoto flattens the planes within the image and brings the background closer.

Conclusion

The main advantage of the 85mm lens is that you can take flattering portraits with it no matter how close-up you get to your model. The 40mm lens introduces a greater sense of depth (the portrait has a more three-dimensional feel) but you have to be careful with distortion. My model also pointed out to me that I was quite close to her when shooting close-up with the 40mm lens. She was okay with it, but a less experienced model (or someone who doesn’t know me so well) might not be.

The wider maximum aperture setting of the 85mm is also a bonus if bokeh is your thing.

The 40mm lens introduces a greater sense of depth to the image when taking three-quarter or full-length images.

While I’m quite comfortable going on a portrait shoot with just my 85mm lens (I like to take the simple approach) I enjoyed using the 40mm lens as well in this case. Switching between the two heightened my awareness of the characteristics of each lens and encouraged me to use each one more creatively. Perhaps that’s the real benefit of using two prime lenses. More lenses (or focal lengths if you have a zoom) to choose from can create confusion, one is perhaps a little too limiting. Two seems to hit a sweet spot.

Further reading

These articles will teach you more about the relationship between lenses and portraits:

Behind the Photo – Portrait Lenses (50mm and 85mm lenses compared)

Portraits in Low Light (using high ISO and prime lenses to take photos in low light)