Canon EF 400mm f/4L IS DO II USM

Using the 400DOii + MB T iv + Sony a6300.
Of interest, ISO 2500 with no NR, sharpening at LRcc default.
If you zoom in and look closely you can see an interesting moire in the
feather detail in some spots. We saw the same thing with the Olympus 300/4
with the OMD m5ii.
I chose Sony a6000 for the POTN listing since a6300 not available yet.

IMAGE LINK: https://flic.kr/p/G2VH​CN

Again using the adapted Sony a6300 via Metabones. The little Sony does ok at ISO 4000 I think But daylight noise is easier than dark noise eh .

IMAGE LINK: https://flic.kr/p/Gs3p​gL

Impressive images. How fast is focus with this setup? Could you capture birds in flight?

Coderunner so far no opportunity to try but my gut says easily yes. I was getting BIF with the a7Rii + LAEA3 + 70-400gii and it has the same limitations (no zone, only Center, AF-C best, and so on). Acquisition of still shots at different distances is way way better than with the A7Rii via Metabones T iv with any EOS lens (and I tried 300/2.8 IS II, 400DOii, and 500ISii. BUT I will say this, in an area where you have widen open spaces where you can see the target/bird coming from some distance, you'll have better odds.
So based on actually getting BIF with the mush slower A7Rii I say adapted EOS lenses and the a6300 are very doable, the a6300's AF system is just so much better AND as you've read no EVF refresh rate problems.
I've also shot BIF with the a6300 + FE 70-200g and it's like cheating. Check out this one-
https://www.flickr.com …6421267592/in/d​ateposted/
I got around 300 hundred shots that day all looking just like this one machine gunning with the a6300.....problem as you'll easily see is lack of focal length.
If Sony would give us a 400mm then they could rock the wildlife/BIF world, on a native e-mount lens the lock-on and tracking is amazing.
We have the FE 70-300 on pre-order, the extra 100mm will help some.

Tomorrow we hope (weather depending) to take Oscar out to a field where we know hawks are nesting. Oscar is a life-size plastic Great Horned Owl which we have adorned with added real feathers...the Red-tails in my area hate GHOs, so we'll see if they swoop him. If so I'll be waiting in a blind....

I look forward to seeing your BIF results. I keep hoping that Canon will produce a killer mirrorless DSLR but I'm not holding my breath.

OK, went out to the field near the trees with the nest. Sure enough that got at least the female out checking us out.
Would I recommend the a6300 + Metabones + EOS lenses? No. But it is doable, just nowhere near as easy as with a 7Dii and a Canon lens.
The challenge is getting the Center focus group on the bird. Wide mode is just too wide and the other modes aren't available with the adapted lens. Now
is it fun trying=yes! Once you get the center group on and if you can keep it on then the combo does fine.
But several times I'd see the hawk in the air, say 100 meters/100 yards away and it would take a while to find and lock on. If the bird was flying near
some tree tops I could prefocus (not manually but back button focus on the trees) and when the bird flew close to the trees I could see him/her and then
get the Center box and the green dancing little boxes on the bird. When i did that I could follow and get 12-15 shots in a row looking a lot like these-

IMAGE LINK: https://flic.kr/p/GsVq​di

IMAGE LINK: https://flic.kr/p/FDaw​7A

^,^^ Forgot to mention that the adapted combo fails big time compared to the native e-mount 70-200, but that would be expected. Hopefully in another week or two the FE 70-300 will be here for a test run. The big advantage of the native is the Zone in AF-C, the Zone is what makes it so easy, and again if Sony would only give us real focal length

Just trying if I can stack 3 doublers without using an ET - 400 DO II @ 3200 mm, f/32.

Incredible.

Impressively sharp. I really want a good mirrorless mainly for wildflowers and landscapes. Maybe there's a Sony in my future

This one a big crop, even with the 'crop factor' and 400mm it was a ways off....still a nice story for me, an irritant for the hawk.
I'm done with the a6300 and adapted EOS lenses for a while. Soon enough the FE 70-300 will be here, maybe another week or two, then
see how it does.

IMAGE LINK: https://flic.kr/p/Grw7​M9

Migration is well underway.
Common Yellowthroat
7D Mark II | EF 400mm f/4 DO IS USM @560mm | 1/500 | f/7.1 | ISO 200

Wow! the ultimate handheld BIF rig

Coderunner wrote in post #17984943
Wow! the ultimate handheld BIF rig

Yup, I can't wait to try it at BIFs. For a Sunny 16 exposure, and using 1/FL to control camera shake, I need to shoot 1/3200 sec, f/32 and ISO 12,800. Manual focus, of course.

Seriously, I was amazed that CD AF still worked at f/32. The combo can actually lock focus in LV when the subject is contrasty.

Coderunner, must report on the a6300. Was out in the yard dinking around....75F bright Sun, just shooting stills and the overheating icon appears on the screen. It didn't shut down but.....
Day before same situation bright Sun 75F, black camera in the Sun shooting 4K video. Camera did shut down after 3-4 vids of 1-3 min's each. Just so you know.
Sony could have embraced white for this body.