EOS R6 Mark II won't take photo with EF lens and adapter

[melblanks42]

Hi there, 

I have a Canon EF 70-300mm f4-5.6 and have just purchased a Canon R6 mark ii with an adapter. The lens fits onto the adapter but I’m unable to take a photo. Just wondering if this has happened to anyone else? 
Thanks, Mel 

[deebatman316]

Are you using the Canon brand mount adapter. 3rd Party mount adapters are nothing but trouble. Stick with the Canon brand mount adapter.

[lusy26demco]

I would suggest you stick with the Canon brand mount adapter. Third-party adapters can often cause problems, and the Canon one is built to work seamlessly with your gear.

-Demetrius
Current Gear: EOS 5D Mark IV, EF Trinity lenses, EF 85mm F/1.8 USM
Retired Gear: EOS 40D, EF 50mm F/1.8 STM, EF 70-210mm F/4
Speedlites: 420EX, 470EX-AI, 550EX, 600EX II-RT

[melblanks42]

Hi there, I’m using a canon brand Mount adapter. 

[shadowsports · Accepted solution]

Greetings,

This lens should function with your R6 Mark II adapted.  You mentioned having it before purchasing your R6 mkII.  So we assume it function on another camera?

Do other lenses work on the R6 mk II?  Was the camera purchased new or used?  We need to confirm its history as well.

Recommended troubleshooting steps. 

Ensure the AF/MF switch is set to AF.  

Test with another camera if possible. 

Reset, your camera's main and custom functions.  Mount the lens and retest.

[FloridaDrafter]

Hello, Mel, and welcome!

I'm not sure this is a close enough comparison, but I have the EF 70-300 II and it works fine on both the R6 and R6 II. It's the lens my wife had when she went from DSLR to MILC.

I know I have the original EF 70-300 around here somewhere, but I can't lay my hands on it to test, sorry 😞 I also have and use the EF 70-300L on my MILC's. What a nice lens.

Newton

[melblanks42]

Thanks, it’s a great lens. I just tested it on another camera and I’m experiencing the same issues. Looks to be something with the lens. I will need to get the lens checked. Thanks for your help. 

[melblanks42]

Thanks, it’s a great lens. I just tested it on another camera and I’m experiencing the same issues. Looks to be something with the lens. I will need to get the lens checked. Thanks for your help

[GazzaQ]

I have just purchased an R6 Mk II with the Canon lens adapter. The whole thing works fine with my old EF 20mm f/2.8 USM, EFS 17-85mm f/4-5.6 IS USM, EF 28-105mm f/3.5-4.5 USM, EF 135mm f/2.8 SoftFocus, and with my EF 50mm f/1.8 STM. However, my Canon 70-210mm f/3.5-4.5 will occasionally not work with the adapter, the camera says Busy and then nothing, can't focus or take a photo. It works faultlessly with my old 30D and 450D.

[March411]

Gazza, the Canon 70-210mm f/3.5-4.5 was released in June 1990, it's a 35 year old lens with 35 year old firmware. Honestly I am really surprised that it will even work occasionally on a MILC.