The-Digital-Picture hacks EF-RF adapter to make all EF lenses work with RF teleconverters

H. Jones · Aug 24, 2020

This is really, really interesting: https://www.the-digital-picture.com...=35054&utm_source=dlvr.it&utm_medium=facebook

Turns out that with a little physical modification, you *can* use the RF teleconverter with an EF-RF adapter to increase the focal length of all EF lenses.

It's unfortunate that there had to be a drill involved to do this, but I'm sure a third party will release a different adapter soon that accepts teleconverters with this knowledge out there. This is super cool, I may buy one of the off-brand adapters, and put a drill to work to try this out.

Fun that the 24-70 turns into a 34-100mm F/4, wonder what other useful combinations there are? I think this would mostly be useful to add another 1.4 extender to any EF lenses you'd want, I'd like to see the RF 1.4 combined with the EF 1.4x for some easy extra reach.

3serious · Aug 24, 2020

R5 -> RF 2.0x TC -> RF to EF adapter -> EF 2.0x -> EF 800mm f/5.6L

someone make this happen and let me know if it autofocuses!

H. Jones · Aug 24, 2020

3serious said:
R5 -> RF 2.0x TC -> RF to EF adapter -> EF 2.0x -> EF 800mm f/5.6L

someone make this happen and let me know if it autofocuses!

Holy crap, since the 800mm f/11 + 2x converter autofocuses on the R5, this could make a 3200mm f/22 with autofocus

zim · Aug 24, 2020

So this would let me use a 70-300L with a 1.4 or 2.0 converter!

I would love to see what the IQ was like with that combo

Mt Spokane Photography · Aug 25, 2020

It probably still would not let me use my 100L with a TC. They seem to be incompatible and go crazy if you can find one that fits.

GMCPhotographics · Oct 23, 2024

It's useful if you want to double stack a TC, eg a EF 2x mk III and a RF 1.4x or RF 2x on say a 300mm f2.8 II L.

meywd · Nov 3, 2024

You can do that now, with the ef ones, ef2x ii extension tube ef2x iii, and you can add as much v ii extenders since they stack

And with my 100-400 on the R3, auto focus works with 1.4x ii + 2x ii + 2x iii

AlanF · Nov 4, 2024

meywd said:
You can do that now, with the ef ones, ef2x ii extension tube ef2x iii, and you can add as much v ii extenders since they stack

And with my 100-400 on the R3, auto focus works with 1.4x ii + 2x ii + 2x iii

With 3 lots of image degradation and f/32, how does the image match up to enlarging 400/5.6 with Topaz?

meywd · Nov 4, 2024

Used Lightroom super res instead of Topaz

100-400 Super Res

100-400 Pure (400mm f5.6)

100-400 IS II + EF 2x III (800mm f11)

100-400 IS II + EF 2x III + EF 2x II (1600mm f22)

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III (2240mm f/32)

Full and crop images can be seen in Album

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III Crop

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III Full

100-400 IS II + EF 2x III + EF 2x II Full

100-400 IS II + EF 2x III + EF 2x II Crop

+2

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III Tests

meywd
Nov 4, 2024
11

AlanF · Nov 4, 2024

meywd said:
Used Lightroom super res instead of Topaz

100-400 Super Res

100-400 Pure (400mm f5.6)

100-400 IS II + EF 2x III (800mm f11)

100-400 IS II + EF 2x III + EF 2x II (1600mm f22)

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III (2240mm f/32)

Full and crop images can be seen in Album

+2

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III Tests

meywd

Nov 4, 2024

11

Thanks!

kaihp · Nov 4, 2024

@neuroanatomist I recall you also modified a 3rd party adapter - I think you also tested it with an RF extender. Which brand and model adapter was this?

Nevermind. I found the post, It was a Commlite EF-RF adapter. Now I gotta find one.

neuroanatomist · Nov 4, 2024

kaihp said:
@neuroanatomist I recall you also modified a 3rd party adapter - I think you also tested it with an RF extender. Which brand and model adapter was this?

Commlite.

RF and EF extenders on the EF 600/4L IS II

After getting both the RF extenders to use with my RF 100-500L, I became curious about whether they would perform better than my EF MkIII extenders when used with my EF 600/4L IS II on my EOS R3. As most will know, the protruding elements of the RF extenders do not fit into the Canon EF-RF mount...

www.canonrumors.com

kaihp · Nov 4, 2024

Looks like the JJC adapter is identical except for the name

JJC EF-EOS-RF LENS MOUNT ADAPTER

goecker.dk

neuroanatomist · Nov 4, 2024

kaihp said:
Looks like the JJC adapter is identical except for the name

JJC EF-EOS-RF LENS MOUNT ADAPTER

goecker.dk

Not really, the one you linked has baffles on the sides that you'd likely also have to trim off. The reason I chose the Commlite is that it has the widest opening of all the 3rd party adapters, meaning less to trim away. The JJC one actually looks worse than most, since most have a round opening while the JJC one has even more stuff to trim away.

Functionally, they're all the same so if all you're looking for is to use EF lenses on RF bodies they'll all work. But if your goal is to use RF extenders behind the adapter, IMO it's better to start with the Commlite.

AlanF · Nov 4, 2024

meywd said:
Used Lightroom super res instead of Topaz

100-400 Super Res

100-400 Pure (400mm f5.6)

100-400 IS II + EF 2x III (800mm f11)

100-400 IS II + EF 2x III + EF 2x II (1600mm f22)

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III (2240mm f/32)

Full and crop images can be seen in Album

+2

100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III Tests

meywd

Nov 4, 2024

11

For amusement, here is your 400mm shot upscaled 6x in Topaz Gigapixel 8, with Generative AI, standard preserve text, standard. (Screenshots, about 70%).

kaihp · Nov 5, 2024

neuroanatomist said:
Not really, the one you linked has baffles on the sides that you'd likely also have to trim off. The reason I chose the Commlite is that it has the widest opening of all the 3rd party adapters, meaning less to trim away. The JJC one actually looks worse than most, since most have a round opening while the JJC one has even more stuff to trim away.

Functionally, they're all the same so if all you're looking for is to use EF lenses on RF bodies they'll all work. But if your goal is to use RF extenders behind the adapter, IMO it's better to start with the Commlite.

Yeah, realized that on the second look. I was going by the round contact points. Found a Commlite here in Denmark. Now I need to buy the used RF 2x TC I've found as well.

Diko · Nov 5, 2024

meywd said:
...
100-400 Super Res
...
100-400 Pure (400mm f5.6)

100-400 IS II + EF 2x III (800mm f11)
...
100-400 IS II + EF 2x III + EF 2x II (1600mm f22)
...
100-400 IS II + EF 2x III + EF 2x II + EF 1.4 III (2240mm f/32)
....

Thanks for sharing....

meywd · Nov 8, 2024

for fun, 2 photos taken 5 months apart.

800mm f11 Super Res

2240mm f/32 Enhanced NR

Diko · Nov 13, 2024

Are these two photos shot on different occasions? According to EXIF they are. So they seem incomparable due to air shifting, @meywd.

meywd · Nov 13, 2024

Diko said:
Are these two photos shot on different occasions? According to EXIF they are. So they seem incomparable due to air shifting, @meywd.

yeah they are, that's why I started with "for fun, 2 photos taken 5 months apart."

The-Digital-Picture hacks EF-RF adapter to make *all* EF lenses work with RF teleconverters

Photojournalist

Photojournalist

EOS R3

Desperately seeking birds

EOS R3

Desperately seeking birds

Desperately seeking birds

30 fps...

EOS R3

800mm f11 Super Res​

2240mm f/32 Enhanced NR​

30 fps...

EOS R3

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The-Digital-Picture hacks EF-RF adapter to make all EF lenses work with RF teleconverters

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