cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

EF mount lenses on R5

Betjothom
Contributor

I currently have a Canon 5 D Mark iv that I like very much. If I purchased a mirrorless and used an adapter with my 400mm f 2.8 would I lose any performance from this lens or others?

18 REPLIES 18

Lotus7
Rising Star

No, not at all. There will be NO performance loss. The Canon adapter has no optical function, but only provides the correct back focus distance required for EF mount lenses and relays the electronic connections for focus, in-lens stabilization and aperture control.

The IS functions of a EF 400 f/2.8 L IS -II or III will integrate nicely with the internal image stabilization of a R5 or R3 and result in a few more stops of IS so your usable slow shutter range will be extended. You should wind up with having a 400mm tele that can be hand held at 1/30 sec. and the improved camera performance may provide faster focusing in low-light situations.

Canon provides several EF to RF adapters at different price points with the difference being the inclusion of a control ring to control selected camera functions at the lens and/or the ability to add filters behind the lens. Optically, they are just empty spacer tubes, so unless you need the additional control ring function, the basic ($100 version) will work well for your lens.

It's important that the mechanical (2) bayonet mounts and the position of the sets of electronic contacts are absolutely correct, so it's smart to use a real Canon adapter instead of any of the "3rd party" models on the market, some of which have proven to be poor fits.

Betjothom
Contributor

This is great information, thank you so very much!


@Betjothomwrote:

I currently have a Canon 5 D Mark iv that I like very much. If I purchased a mirrorless and used an adapter with my 400mm f 2.8 would I lose any performance from this lens or others?


Lotus7 is spot on. I don't have the EF 400mm f/2.8L is USM III (if that's what you are referring to), but I have a bunch of EF L and non L lenses, from 24mm to 100-400mm, that work just as well on my R5 & 6 as they did on my 5D mark IV and 7D mark II, maybe better, but that's probably the cameras. However, RF L lenses are a step up from their EF counterparts, enough so that I have replaced almost all of my EF lenses with the RF versions, or as close as I could get. It's just better suited to the R. I consider the RF counterparts to be "mark XX" to the EF's, if that makes sense.

My original plan was to just adapt my EF lenses, but after buying the first RF, that plan changed.

Newton

Betjothom
Contributor

Thank you, both replies are most helpful. Lots of decisions to make.

Waddizzle
Legend

According to my sports photographers friends and countless rumors, you may actually see an improvement in performance with the R5 and R6 mirrorless bodies.

--------------------------------------------------------
"The right mouse button is your friend."

Betjothom
Contributor

Wow, didn’t see that coming! Thank you for that insight!

Lotus7
Rising Star

Waddizzle: "...you may actually see an improvement in performance with the R5 and R6 mirrorless bodies."

That seems to sometimes be the case and is most likely due to the difference due to the fact that focus in mirrorless cameras is achieved through actually achieving absolute lens to focal-plane focus using the image sensor in a mirrorless body, as opposed to the indirect method of using a partially silvered mirror to reflect the focus points to a separate focus array in a DSLR. This necessitates a need for focus calibration "tuning" which may create subtle focus errors. Those are not usually significant when smaller apertures are in use because of the depth of the back focus plane. However, when very large apertures are used and/or long focal length lenses are brought into the system, the back focus range becomes so "thin" that even tiny focus calibration errors may affect image quality.

The other obvious factor is the constant improvement in actual image sensor and micro lens component performance in newer bodies.

Overall image quality is not determined by lenses, or sensors alone, but is a function of the whole imaging system. Focusing by direct measurement of image content on the same sensor as is producing the final image totally eliminates the possible (actually probable) mechanical errors in a focus system that depends on bouncing light off a hinged mirror onto a focus sensor in a different location than the actual sensor that will record the image. That's one of the major advantages of mirrorless imaging.

Waddizzle,

I agree. My adapted EF glass is amazing on the R5 C. Even the Sigma is great in Photo Mode. Its Cinema mode when Canon glass matters. People who are using the R5/R6/mkII will never experience this.

@Betjothom,

You will buy RF lenses (I promise you). I loved the EF~70~300 adapted on my R5 C. Then I put a RF100~400 on it. Weight savings alone is a game changer. It practically balances on one finger. That's the one thing I will not miss about my EF lenses. Yes they are built like tanks, but RF glass is still exceptional quality and lighter weight.

~Rick
Bay Area - CA


~R5 C (1.0.2.1) ~RF Trinity, ~RF 100~400, +Canon Control Ring

~6D2 (v1.1.1) Retiring ~EF Trinity, others ~DxO PhotoLab Elite ~Windows10/11 Pro ~EVGA RTX 3080Ti FTW3 Ultra ~ImageClass MF644Cdw ~Pixel6 ~CarePaks Are Worth It

Thank you. Yes the weight factor is definitely a plus and as I’m an older adult my joints don’t always hold up to the weight and strain of the heavier equipment.

Announcements
01/18/2023: New firmware version 1.1.1 is available for EOS R6 Mark II
01/09/2023: Help ensure your autofocus is properly aligned with a Canon Precision Alignment
01/03/2023: Welcome to CES 2023!
12/08/2022: New firmware version 1.0.5.1 is available for EOS C70
12/07/2022: New firmware version 1.7.0 is available for EOS R5
12/07/2022: New firmware version 1.7.0 is available for EOS R6
11/22/2022: New firmware available for EOS R3, EOS R7 and EOS R10
11/16/2022: We're thrilled to be ranked among the Best Employers for Veterans in 2022 by Forbes.
08/31/2022: New firmware version 1.1.1 is available for RF 70-200mm L IS USM
08/09/2022: New firmware version 1.2.0 is available for CR-N 300
08/09/2022: New firmware version 1.2.0 is available for CR-N 500
07/14/2022: New firmware version 1.0.1 is available for CR-X300
06/10/2022: Service Notice:UPDATE: Canon Inkjet Printer continuous reboot loop or powering down
06/07/2022: New firmware version 1.3.2 is available for PowerShot G7 X Mark III
05/31/2022: Did someone SAY Badges?
05/26/2022: New firmware version 1.0.5.1 is available for EOS-C500 Mark II
05/26/2022: New firmware version 1.0.3.1 is available for EOS-C300 Mark III
05/10/2022: Keep your Canon gear in optimal condition with a Canon Maintenance Service
05/05/2022: We are excited to announce that we have refreshed the ranking scale within the community!
04/26/2022: New firmware version 1.0.1.1 is available for EOS R5 C
03/23/2022: New firmware version 1.0.3.1 is available for EOS-C70
02/09/2022: Share Your Photos is back!
02/07/2022: New firmware version 1.6.1 is available for EOS-1DX Mark III
01/19/2022: READY FOR ANYTHING EOS-R5 C
01/13/2022: Community Update. We will be retiring the legacy profile avatars on 01/20/2022. Click this link to read more.