Autofocus: Let’s start with the biggest change in the Mark 3 from the Mark 2. I could write something sarcastic like ‘Canon forgot to put AF in the 5D Mark 2, but they definitely didn’t forget it in the Mark 3.’ But that’s not my style. Let’s just say that the Mark 2 AF was a big disappointment and to me (and many other photographers) and that I have spent many moments swearing out loud (or grumbling under my breath in front of my kids) about how lame the AF is in the Mark 2. The Mark 3 AF is so improved that my kids will no longer think I can’t complete a sentence when I’m taking pictures.
The autofocus is fast and accurate…if you know how to use it. If not, it’s just fast. I’ve found it works best for me when I select one focus point only, knowing exactly how I’m going to compose my shot. The cross pattern selection option I find usually front focuses on something I don’t want, so I generally avoid it. The option to select 9 AF points in a square arrangement works well for tracking large moving subjects. Finally, I find the AF option that selects all 61 AF points fairly useless for me. The algorithm on just about any autofocus system it to focus on closest object. I rarely will compose to emphasize the closest object in the frame. I shoot often with the 50mm/1.4 or 85mm/1.8 lenses, which have very shallow depth of field. I have yet to find a camera that can focus those two lenses consistently accurate. But the Mark 3 is really good at doing just that. So much that I’ve even shot running photos with the 85mm/1.8 wide open. Astounding.
What’s not to like about the new AF system? Not much but there is one thing that still needs work…expanded coverage of the image frame. The AF points are still clustered too closely to the center of the frame. My style of shooting is to put subjects towards the edges of the frame. With a moving subject or a shallow depth of field, prefocusing and recomposing is not an option. Also, I shoot a lot of backlit scenes and find the AF loses a lot of its advantage. I hope you’re listening Canon!
New screen: It’s gorgeous. In fact almost too nice. I’m really nitpicking here. How can I be complaining that the screen is too nice? I often find the screen makes my images pop more than my high end LaCie monitor that I edit on. I know that part of the reason for that is the picture style settings in my camera. I edit in Photoshop, which doesn’t see Canon’s picture style settings. That’s responsible for part of the difference. But the difference is also because the way the screen displays saturation/contrast.
But the screen is very sharp and bright. It’s more useable in bright daylight than any screen I’ve used before, which to say that it is useable but still not easy, especially on a sunny day in the snow. One thing that Canon did that for me is a simple yet huge improvement is to give a white border around the levels diagram when reviewing images. In the past, it was a black background on the levels diagram against a black screen background, making it impossible to tell where the top and bottom ends of the levels were, especially when viewing in bright sunlight.
Speaking of reviewing (or chimping) images, Canon has changed the zoom feature on image review. In the past, there were two buttons on the top right of the camera whose function was dedicated to zooming in/out. This was fine although a bit cumbersome (push and hold or push, push, push to zoom in). Now, there is a dedicated zoom button on the left of the screen. Push it once to enable zooming. Then use the shutter dial to zoom in/out much faster. This took a little getting used to but I do like it better if for nothing else it’s much faster to zoom all the way in. The only drawback for me is that when I switch cameras (often during a shoot), when I chimp, I forget which one I’m using and fumble around for a few seconds until I remember which camera I’m using. Chalk that one up to operator error.
Image Quality: As good as it gets, really. Slightly improved over the Mark 2 but that was the best thing about the Mark 2. 22MP is a lot of resolution and my clients will regularly make wall size enlargements (for trade show booths) that look amazing, even up close. The level of detail is incredible for a 35mm sensor.