topic EOS C100 Mk II lens release pin has now failed on two cameras in Professional Video

EOS C100 Mk II lens release pin has now failed on two cameras

jenshaulund — Mon, 28 Apr 2025 15:58:43 GMT

Hi everyone. I have two C100 Mk II cameras that I use on a regular basis.

Six months ago, I could not remove the lens from one of the cameras due to the pin that secures the lens not being retracted from the EF mount when pressing the release button. I sent it in for repair with the lens attached and received it back after paying $500 for the service.

Now my second C100 Mk II has the exact same problem. The lens is stuck. According to Canon this is not a known issue.

What do you guys say - am I the only one with this issue. Looking forward to reading your comments.

Cheers,

Jens

Re: EOS C100 Mk II lens release pin has now failed on two cameras

shadowsports — Mon, 28 Apr 2025 16:07:21 GMT

Greetings,

Are you using a Canon lens?

Re: EOS C100 Mk II lens release pin has now failed on two cameras

jenshaulund — Mon, 28 Apr 2025 16:20:33 GMT

Hey Rick - Yes, a Canon EF-S 18-135mm f/3.5-5.6 IS STM. Now you mention it, that was the same type of lens that was on the other camera when it failed. I've been using that lens for years. In many cases I use that type of lens on both cameras - never had an issue.

Re: EOS C100 Mk II lens release pin has now failed on two cameras

hsapien — Mon, 09 Mar 2026 02:37:36 GMT

Hello Rick! I now have the same problem where my Sigma 18-35 won't come off. The lens release button doesn't go down far enough to release the locking pin. Since you had this problem twice, and at least one other person had this same problem, I wonder if the pin is too long and needs to be shortened a tad. There are several visible screw heads that appear to attach the lens-mount assembly to the main body, but am hesitant removing these since there probably is a gasket to help with water-proofing. Also, once it's off the lens may have to be disassembled to get it off the mount !

Has anyone else had this problem and if so what is the easiest way to remove it. I could sacrifice the lens, but don't really want to do that.

Re: EOS C100 Mk II lens release pin has now failed on two cameras

hsapien — Mon, 09 Mar 2026 02:41:26 GMT

I should mention this is the first time I put this lens on the C100, which was recently purchased. If I ever get it off, I will grind the pin down a little.