So I finally got my R7 and now Im stuck on the glass. I was looking at those RF 600mm and 800mm f/11 primes because the price is honestly great for my $1200 budget but then I read a bunch of reviews saying the small aperture is a nightmare for morning shots. I'm heading to Yellowstone in three weeks so I need to decide fast.
My logic was that the crop factor gives me crazy reach anyway but then people keep mentioning the old EF 400mm f/5.6 with an adapter. It’s older tech though so I’m worried it wont keep up with the R7 autofocus system. Should I stick with the modern RF primes or go the adapted route for more light? I really just want something sharp for bison and bears...
In my experience, f/11 is a total nightmare for Yellowstone dawn. Ive tried many setups over the years and honestly, the Canon EF 400mm f/5.6L USM is still a beast. The AF is surprisingly snappy on the R7 with the Canon Mount Adapter EF-EOS R. Its way sharper than those budget RF primes and that extra light is a lifesaver for bears... go the adapted route.
To add to the point above: I have been very satisfied with the Canon EF 300mm f/4L IS USM for wildlife. It works well on the R7 because that f/4 aperture is so much more versatile than the f/11 options when you are shooting in the early morning light at Yellowstone. I have had no complaints about the AF tracking speed when using the adapter; it is snappy enough for moving animals and the sharpness is quite impressive for older glass. One quick tip for the R7: keep an eye on your ISO. Even though f/4 is better than f/11, that sensor has very small pixels and noise can creep in fast. I usually find that sticking to a slightly shorter prime like the 300mm and cropping in post works better than using a darker 800mm that forces your ISO too high. It is a very practical way to maintain image quality while staying within your budget.
Man, I am struggling with this exact same thing for my R7 and it is honestly so draining. You spend all this money on a body with an amazing sensor and then the lens options under 1200 bucks are all just compromise after compromise. It really sucks because you just want to be ready for those early morning grizzly sightings and every path seems blocked.
- Sigma 150-600mm f/5-6.3 DG OS HSM Contemporary: It gives you that f/6.3 which is better for light than the primes you mentioned, but then you have to deal with the adapter and that annoying focus pulsing issue that R7 users always complain about. Plus it weighs a ton.
- Canon RF 100-400mm f/5.6-8 IS USM: The autofocus is way more native and snappy than any adapted glass but f/8 at the long end still feels like a massive sacrifice for dawn shots when you need all the light you can get. It just feels like you cant win. Either you get a slow native lens or an adapted one that might glitch out on you. Its just a bummer when youre trying to prep for a big trip like Yellowstone and nothing feels like the right call... really takes the fun out of the gear search.
