A real review by an in-the-field photographer.
I am primarily a bird photographer, so the ASP-C sensor size is a plus for me, so this isn't about full frame versus smaller size sensor. For me it's about shooting action, motion, focusing quickly and accurately and about getting the bird large enough in the frame. Since birds are small, magnification or reach is important.
I took the Canon 7D Mark II up to the Skagit to see what it could/would do. Here are a few images and a few lessons learned about this camera.
When I got out of the car at the Snow Goose Preserve I knew it would be a special morning. I just had to wait for it. The moon was bright and gorgeous, the fog was pink, the air brisk, and a little patience was in order. I waited for some birds to fly in front of the moon, and after a while this flock did. If these snows had flown by 10 minutes, earlier the sky would have been pink. Oh well, next time. ISO 800 doesn't seem to matter much; there's a little grain from the higher ISO but there isn't any noise, and I can live with a little old fashion Ektachrome look every once in a while.
The Rough-legged Hawk was pretty far away. Even with an effective focal length of 1,344 mm I still had to crop this by about 40 to 50%, but it shows what the new camera can do. That, and it was the first Rough-legged Hawk I saw this year in the Skagit, so I felt like I just had to get a shot of it.
Not my best shot, but I include it to show what f/45 at ISO 4000 and a 600 mm lens looks like with the Canon 7D Mark II. Typically at f/4 or even f/8 there is an inch of depth-of-field, at f/45 there's about a foot. If I could have gotten on the other side of them and they weren't backlit, well then it could have been an okay image. I'd still have a problem that they're in the mud etc. but you can see the possibilities. Oh, and I'm pretty sure this is the first time I've taken and shown an image at ISO 4000 and f/45!
As I pulled up to this Great Blue Heron jumped up and started flying off. I got off a couple of quick shots. The Canon 7D Mark II acquired the bird quickly and the ten frames per seconds functions are what allowed me to get a few images. If I had been shooting the Canon 5D Mark III my other camera, I simply would not have gotten any images at all. Not the best image, at f/8, with the Extender, the smaller camera sensor, and the shooting angle from the road, all made the background a little too much in focus and thus distracting, but again you can see the potential of the new camera.
So with just the camera and the 600 mm lens, the effective focal length was 960 mm. That's a lot of reach when a big bird like a Red-tail is just across the road.
Okay, I've had the camera about ten days, and I still like it. I'm going to be using it as my primary bird photography camera with the 5D Mark III relegated to landscapes and a backup bird camera. The autofocus is fast, the ten frames per send are fast, the autofocus is everything Canon said it would be, the new sensor is pretty darn good. One thing the extra reach of a smaller ASP-C sensor will do for bird images is the photographer doesn't have to get as close, so the birds appear in a more natural stance, they aren't all hunched over ready to launch themselves away from the perceived threat of a photographer. Hope this helps you if you're trying to decide if this is the camera for you.