7dmk2 or 5dmk3 for birds?

So I finally decided to upgrade my camera. I have a 1dmk3 (that I am keeping) and 6D that will help fund my next purchase. I pretty much just have my canons for portaits with my 85mm, kinda close wild life or zoo pictures with my 300/4 IS, and I can also borrow a 400DO or 500L from my friend which is awesome. I am not very sure about which has better AF for tracking and such, so what are your experiences with these two? I like the 1D style body but it seems the 1dmk4 is getting pretty old now. For now I am obsessed with humming birds and I usually hang out at the local lagoon taking BIF pictures.

I'd go with the 7d2. Crop sensor gets you some extra reach. Very good AF and fast frame rate which is great for birds in flight. I've loved mine. The 5d4 has a very good AF system, but the 5d3 AF and frame rate is not near the 7d2.

The 5d3 utilizes a variant of the 1dx AF system and is very capable.

I have both. Right now I am trying to figure out why I get better images off the 5D mkiii vs the 7D mkii. This is assuming things are equal and the frame is filled the same or close too. I get that the 5D mkiii's more total pixels and 7D mkii's crop all come in to play as far as equal framing once on screen or in print.

Shaun Liddy wrote in post #18629149
I have both. Right now I am trying to figure out why I get better images off the 5D mkiii vs the 7D mkii. This is assuming things are equal and the frame is filled the same or close too. I get that the 5D mkiii's more total pixels and 7D mkii's crop all come in to play as far as equal framing once on screen or in print.

If you are filling the frame about equally, then I'm pretty sure the 5D3 would be better.

But most of the time in bird photography, we are reach-limited, so the framing would be different. The 7D2 would win out.

For hummers and other BIFs you want a camera with high FPS, like the 7D2 or 1D4. The high FPS gives you lots of pics to choose from so you don't miss that perfect frame. Depending how close you can get to your subject and lens size, crop factor is also a factor. It sounds like you have ample lenses to choose from.
Don't get caught up in how many AF points one camera has over the other. Use the tiny one in the center and put it on your subject.

P.S. Of course, LVMoose may have a different opinion.

Today's side by side shows my 5d mkiii renders details better than my 7d mkii

https://photography-on-the.net …/showthread.php​?t=1496567