Re: NEX-EA50 equal to Canon 5D???
 

I fail to see how focus is going to be THAT much of an issue with ring fighters. One of the advantages of having a APS-C sensor is that you have to work for your DoF. This means that if you need clean, in focus shots like sports, you're going to have more leeway. I would just set it to manual, set your focus to the middle of the ring, and forget it. You'll probably be far enough distance away that your DoF will be quite a few meters. Many auto-focus's will be fooled by the fence or cage, anyway. The facial recognition seems to be good enough on the EA-50 that I bet it would do a fairly good job compared to most. The AF's slow speed is only a problem when it's making large adjustments.

Where the EA-50 would probably fail would be on a race car circuit getting incredibly quick changes in distance.

Re: NEX-EA50 equal to Canon 5D???
 

Hi Eric

It's wouldn't be the wide shots that need attention..it would be the tight closeups ...stick a wide lens on the camera and yes, focus in the ring centre and provided the DOF is sufficient, everywhere the fighters go will be in focus. The standard procedure to to fix your wide camera so it covers the ring totally and use that as your main timeline (you could also just use a GoPro which is always in focus and would look cool shooting from a fairly high angle)
Then just do the close ups by hand ...you are only using them to add interest to to the action so the bits where you are "getting" focus can just be cut out and then do cut ins of the clean footage and overlay that on your wide footage.

Chris

Re: NEX-EA50 equal to Canon 5D???
 

If you would use a large f-stop, a wideangle lens that can't zoom then yes, that would be an option, but then you just as well could stick a go pro to the corner of ring. Even with the stocklens focus can be tricky and you notice right away if it's off, even for a slight bit. You might not notice in the viewfinder but you sure will on a big screen. A lot depends on where you stand, how close the fighters will be to you when they move around, how much light you have and if you use any zoom. All factors that will give out of focus shots, the autofocus is also too slow to follow any quick changes, it will get there eventually but by that time the fighters might have moved to another position. :)