Like many other amateurs, I have been closely following every available breadcrumb on this new offering. I am greatly interested, as I think I'm ready to finally let go of my three old super teles and replace with some new tech to mount on my R7. Also like many others I'm weighing this against the already popular 100-500 L.
Initial youtube vids are somewhat promising, but sadly I haven't seen enough yet to sway me 100%. I'll go on record saying that the f9 max aperture does not scare me, because the R7 seems to have an AF algorithm that is next level compared to older phase style EF bodies, clearly demonstrated by the 600mm and 800mm f11 lenses. Also, I'm certain with proper field technique and subject placement, nice b/g blur should be easy to produce with such a heavily compressed focal length.
I will say, most of the images I've seen at 800mm fall just a slight underwhelming. Something I've struggled to put my finger on. Just a tad lacking in contrast. I think the problem is that all the images are being resized for web, or in particular YouTube, making it hard to judge nominal sharpness. I just noticed The Digital Picture has uploaded some resolution crops for the lens here:
The-Digital-Picture: Canon RF 200-800mm F6.3-9 IS USM Lens Image Quality
Judgement is left for the eye of the beholder. It's entirely possible these are taken with a pre-production example. Bryan doesn't mention this on his site, I just know this is always a possibility with early hard to get lenses. So keep that in mind.
I really need a safari style lens that gives me reach, but also backs down in fl so I can get compressed landscapes, or animals in their environment. My old Sigma 150-500 OS is the best all around lens I've ever used for travel around the world, due to it's excellent range. That lens just doesn't get used anymore because it's not sharp (at all, LOL), and struggles to AF with predictability on the R7. My other lenses are sharp, but they are primes. I'm more of a run and gun shooter most of the time, so I don't prefer to travel with the primes, plus I don't like using two bodies at the same time if I don't have to because of the bulk. Of course I love the 800mm capability of this lens, but I wonder if the price point is just too much of a compromise. But compromise is always the name of the game, and I think it's an important part of the expectation here. I'm eager to see more real world shots with this new super zoom, and hope to have access to SOOC files. But I'm starting to wonder if cropped images from the 100-500 will still be superior to uncropped images with the 200-800. It is an interesting offering for sure. Just thought I'd pass along the link for anyone interested in seeing contrast and sharpness.