Answering the Question - Canon 5D Mark III versus Olympus OM-D E-M1

A little while back I asked myself on this blog if I should keep my Canon 5D Mark III after I got my Olympus OM-D E-M1. In short, I was wondering if it was worthwhile keeping the Canon if the Olympus is easier to carry and can deliver the kind of experience and results the Canon could. Olympus tells me I was one of a lucky handful that got their E-M1 early and so I have had little more than a week to seek the answer to my question.

A week isn't very long, but in the that week I have tested the areas that matter most to me, which are resolution, performance in the studio, low light and autofocus. Like in my other posts, I have tested in situations that are similar to the ones I normally shoot in. These tests are thus not exhaustive. Also. I haven't shot any video.

I won't discuss some glaring differences between the two cameras, such as price, weight, bulk , stabilization and availability of lenses and accessories. I assume my readers are well aware of those considerations.

Neither am I sharing my pure test shots with you. They're boring. Plus, I think any blog can only host a limited number of pictures of puppies or passing cars.

Let's go.


Olympus OM-D E-M1

The Canon wins, no question about it. I used my better Canon lenses and my better Olympus lenses and in all cases the files of the Canon are markedly sharper at 100% on my monitor. In model photography that doesn't matter that much, because there's only so much sharpness you want, but in landscapes it matters. Tree trunks, fall leaves and rock formations resolve better on the full-frame Canon sensor than on the much smaller Olympus MFT sensor.

How much better? This is where push comes to shove. On small prints or JPEGs, you can't tell the difference, but I hope you don't buy these kinds of cameras if all you want to make are small prints or show little pictures on the web. On 13x19 prints the difference is hard to tell from a normal viewing distance. When looking closely, there's a bit more resolution in a picture of a forest line, but no discernible difference in a portrait. I can't print larger than 13x19 at home, so I will have to order a few larger prints to see how much the difference matters in the real world.

Low Light

Canon 5D Mark III

Again, the Canon wins. The Olympus does well in low light, but the Canon shows less noise. With the Canon, you have more leeway. In most circumstances the Olympus will serve you well in low light, but when there's an extra challenge or you plan to shoot quite a bit in dimly-lit environments, you need the Canon.


Another win for Canon, but not necessarily a deal breaker for the Olympus.

Single Auto Focus is fast in flawless on both cameras. I don't own any Olympus Four-Thirds lenses, so I can't speak for those, but the MFT lenses I own all focused very fast and were spot on. The Canon, of course, was without problems in this regard as well.

Continuous Auto Focus is where the differences show up, as was to be expected. The Canon locks on quicker and stays with the subject more consistently than the Olympus. The Canon also is quicker to find the subject again after one or two shots get out of focus. Both cameras become weaker in this regard as the subject gets closer, but that's to be expected.

On both cameras you can limit the focus points to certain segments and this improves the speed and accuracy as long as you manage to keep your subject within the chosen area.

Still, the Olympus does a good job. If you're shooting sports in low light and from relative close distances, the Canon is your better bet. If you're working pretty far away and have some leeway with your aperture, the Olympus performs admirably.

Personally, since my kids aren't running through the house anymore and I don't shoot sports, the autofocus on the Olympus is plenty good for me.

With focus tracking, a feature the Olympus offers but the Canon doesn't, you focus on a subject and the focus point in theory stays with the subject as it moves through the frame or as you move the frame.

In practice, I found that the camera loses tracking on a pedestrian if another pedestrian crosses the first pedestrian's path. The tracking jumped over to the second person. When tracking our new puppy in the garden, the camera tracked but the focus point shifted to the side of the dog where the fur had the most contrast instead of staying on the dog's head. There might be occassions where it comes in handy, but I don't see myself using it.

Studio Work

Olympus OM-D E-M1

They're both perfectly fine. I'd prefer the Canon, but merely because in a studio I don't have to lug my gear around and I might as well use the camera with the higher resolution. Even though a model's face doesn't need to be completely sharp, you want maximum sharpness in the eyes. But I would have no problem only using the Olympus in a model shoot.


The Canon clearly beats the Olympus. As it should.

But the question was whether I could ditch my Canon and live without full frame.

I don't think so, actually. There are times when it's nice to get the extra resolution that a full-frame camera offers or to be able to get maximum image quality in low light. It's also good to have a camera that can do it all, or almost all, as the Canon 5DIII can.

If you're shooting action, I'd surely keep the Canon. MFT isn't there yet.

The Mystery Somewhat Explained - Olympus OM-D E-M1

But I am looking at DSLRs in a new way. I no longer regard them as my go-to gear, like I have done ever since I started dabbling in photography. I now regard my 5D as a kind of poor man's medium format, a system I'll use when I really need it and don't mind carrying it for that purpose. On paper, it actually makes sense to then get the most out of full-frame and get the Nikon D800(e) with even more megapixels than the Canon. In practice, the quality difference between the two seems relatively small.

This shift in thinking about full-frame DSLRs now leads to a rethink in what lenses I actually need. I have a whole range of lenses for the Olympus, because that's the system I'll use the most under different circumstances.

But for the Canon, I only need lenses that perform well during landscape shooting, on model shoots and in low light. This problably means that I will sell some of my Canon lenses and maybe replace them with  Zeiss lenses.

For you, the answer might be different. If I were to shoot weddings, I'd have to learn more about Olympus' flash performance, for example. For sports, I'd stick with the Canon. Blowing up images beyond 13x19, also the Canon.

By John van Rosendaal