Advice on gear for Kenia Safari

Hello all, i'm a bit struggling right now what i should do.I have the following gear available for my upcoming Kenia Safari:300mm 2.8 I IS, 1.4x , 2x III, 70-200 2.8 II IS, 17-55 2.8 IS, 10-20 Sigma and currently a 7D only. I plan to get a second (back-up) camera but can't make up my mind if another 7D would be okay or change priorities, get an 5D iii and "convert" the 7D to back-up camera.As i don't have any UW or Standard zoom for FF i would have to use the 7D for UW, Standard and 70-200 zoom. The potential 5d iii would be used with the 300mm + 2x (or 1.4x).Do you think that makes sense with respect to Picture quaility and Overall Performance? Or would the second 7D sufficient. Any advice is highly appreciated. Best regards Markus

I own the 7D and the 5D MkIII and use the 5D3 as my primary and the 7D as the backup. The 5D3's AF system is considerably more accurate, consistent and flexible than the 7D's. Also, the high-ISO performance of the 5D3 is a stop or two better than the 7D. You'll consider the 5D3 a major improvement.

When I was last in Kenya (it has a Y) I had a 5D2 and a 7D. I had been using both cameras for several years by then, but during this trip I found the high-ISO performance of the 7D a major problem. The 7D had the advantage of 1.6x crop, but I was happier taking 5D2 shots and cropping in: the only reasons I kept using the 7D during the trip was its superior AF and higher frame rate.

Subsequently I sold the 7D, and these days use the 5D3 with the 5D2 as a backup/2nd body. The 5D3's IQ is much better than the 7D, the AF is superior for action, and the 6 fps frame rate is good enough for me even compared to the 7D's 8 fps. I recently swapped bodies with a 7D user during one of my workshops shooting BIF, and it was enlightening. I could still use it, but the 5D3 was much more enjoyable to use and the images were better (especially at 800+ ISO).

Your lens lineup looks reasonable for a trip like that with a 5D3 for the long lenses. Obviously a 2nd 7D body would be cheaper, but I think the 5D3 would be a better investment to enable your craft. You shouldn't have any hassles switching between the bodies during the day.

Keep in mind though that just as the 7D's AF system was dramatically different from earlier bodies (in terms of configuration and use), the 5D3's is another step forward. Make sure you spend enough time experimenting and deciding on the configuration which suits you. And whichever body you get you'll want to AF-calibrate it against your lenses, etc. Hopefully you've got enough time before your trip.