R/R6/R5 AF difference with TCs

[Jayson]

Say, I have been using my R with a 2.0tc vii with my 100-400 vII. I don't want to buy the Rf mount 2.0 tc as I don't have any R lenses. What I am wondering is if I will see a AF difference if I upgrade to a 2.0 tc VIII over my vII? I know IQ is better using the VIII, but just curious is the AF has any type of benefit. Not really sure if anyone has this issue, so thought I'd throw it out there.

Thanks,
Jayson

[Joel Eade]

The Version III 2.0 TC does have upgraded electronics compared to Version II.

I think the overall performance is somewhat dependent on the lens you are using.

I have a version III 2x TC and it performs very well with the 600mm f/4 II in terms of sharpness, it does slow AF speed a bit but not enough to be a huge problem.

I do have the 100-400mm II lens but have never tried the 2X TC on it.

Here is a link to Bryan's review:

https://www.the-digital-picture.com/Reviews/Canon-Extender-EF-2x-III-Review.aspx

[Joel Eade]

https://joeleadephotography.zenfolio.com/img/s/v-10/p3687567515-3.jpg
Canon 1DX
600mm f/4 II + 2.0 TC III
iso 3200
f/8
1/1000 sec

[Kayaker72]

The R5 with EF 2xTC III does work, but whereas the 1.4x TC III is virtually seamless, the 2xTC is noticeably slower to AF and there is some loss of IQ. On the 1DX III, the 2x TC was solid. Much improved over the R5.

[Joel Eade]

I took these images this morning with the R5 + EF 100-400mm II + 2.0 TC III + EF-RF adapter.

It was heavily overcast so I had to use higher ISO and lower shutter speeds than I would ordinarily like but I think the combination is usable for perched birds.

The AF is only slightly slower, the eye tracking works perfectly and all focus points are available.

One note .... when zoomed all the way to 400mm you end up with an 800mm f/11 lens .... so I don't know how this combo would compare to the RF 800 f/11.

The RF 800 f/11 is a bit more expensive than the 2X TC III especially if you can find a good used one. Also would be less versatile.

The 100-400mm II without the 2XTC is quite a bit sharper but I have no doubt that good images can be made with this combination, especially in better light than I had this morning.

I do not have a version II 2X TC to compare.

https://joeleadephotography.zenfolio.com/img/s/v-10/p4111715506-2.jpg
800mm f/11 1/250 iso 4000

https://joeleadephotography.zenfolio.com/img/s/v-10/p4111715501-2.jpg
541mm. f/10. 1/125. iso 3200

https://joeleadephotography.zenfolio.com/img/s/v-10/p4111715526-2.jpg
800mm. f/11. 1/250. iso 4000

https://joeleadephotography.zenfolio.com/img/s/v-10/p4111715505-2.jpg
556mm. f/10. 1/100. iso 3200

https://joeleadephotography.zenfolio.com/img/s/v-10/p4111715478-2.jpg
482mm. f/10. 1/125. iso 3200