topic Re: Canon R5ii and Rokinon 14mm problems in EOS DSLR & Mirrorless Cameras

EOS R5 Mark II won't take a photo with a Rokinon 14mm lens

shawl — Fri, 09 May 2025 13:33:48 GMT

I am trying to use a Rokinon 14mm f/2.8 ED AS IF UMC with AE chip lens on my Canon R5 Mark ii that was purchased new in 2018 for use with a Canon 5diii. (The lens is still available and, from the B&H site, is NOT recommended for the R5ii!) Lens is manual focus without stabilization. Lens is fine with my Canon 5d mark iv. Proper Canon adapter is used. When the shutter is depressed, it seems via sound that an image has been taken; the red recording light goes on but nothing happens...camera is locked up until the battery is removed to reset.

I have tried a number of things: release shutter w/o lens turned ON; when I checked to be sure the focus mode was manual, it was. When I checked to be sure image stabilization was off, it was.

None of this allowed a picture to be taken.

Perhaps nothing can be done, but if anyone has further suggestions, that would be appreciated.

Re: Canon R5ii and Rokinon 14mm problems

shadowsports — Wed, 02 Apr 2025 01:24:02 GMT

Greetings,

I have the non AE chip version of this lens. I used it on my 6DmkII. It also worked adapted on my R5 C in stills mode (manually) I never tried video and have not used it since I purchased a RF15-35..

Given the manufacturing dates between the two I'm not surprised the lens doesn't work. You'd think it might in manual mode though. It sounds like you done everything you could. You can contact Rokinon and see what they say. Maybe they can assist.

Re: Canon R5ii and Rokinon 14mm problems

shawl — Wed, 02 Apr 2025 01:37:14 GMT

Thanks, Rick.

Steve (SF Native!!)

Re: EOS R5 Mark II and Rokinon 14mm problems

shadowsports — Wed, 02 Apr 2025 14:35:27 GMT

Heads up. It looks like an RF 14-28 f2.8 Z is coming. No date yet, but the rumor is out there.

Re: EOS R5 Mark II and Rokinon 14mm problems

zailgan — Fri, 09 May 2025 02:44:50 GMT

Recently purchased Rokinon 35mm 1.4 and try to use on R5m2 with adapter and have the same issue. I have R5 and it works on R5. What is principle difference between R5 vs R5m2?

Re: EOS R5 Mark II and Rokinon 14mm problems

Waddizzle — Fri, 09 May 2025 04:35:42 GMT

Can you capture stills? You cannot use any shooting mode where the camera attempts to control the aperture. This means only use Av or M modes.

Re: EOS R5 Mark II and Rokinon 14mm problems

zailgan — Fri, 09 May 2025 06:17:50 GMT

Yes I can capture stills and use any mode but it works only for R5. R5m2 when I connect Rokinon lens doesn't show aperture and after press shutter button freezing with saving image light on. Removing and put battery back restore camera.

R5 works well with the same Rokinon lens for all modes.

I think the problem is R5m2 can't control aperture for this lens, but R5 somehow doesn't have such problems.

Re: EOS R5 Mark II and Rokinon 14mm problems

shawl — Fri, 09 May 2025 06:25:05 GMT

weird! Thank you.

Re: EOS R5 Mark II and Rokinon 14mm problems

Waddizzle — Fri, 09 May 2025 09:47:55 GMT

“ I think the problem is R5m2 can't control aperture for this lens, but R5 somehow doesn't have such problems. “

Of course, the camera cannot control the aperture. It’s a fully manual lens. No camera can control the aperture, despite your claims to the contrary. You should only use Av or M models with fully manual lenses.

Re: EOS R5 Mark II and Rokinon 14mm problems

zailgan — Fri, 09 May 2025 13:31:39 GMT

This Rokinon has manual focus but diaphragm is automatic. So it’s not fully manual lens. Lens has only focus ring. By some reason it doesn’t work for R5m2 and worst scenario camera becomes locked, that indication of some problems in firmware. Camera should handle it properly and return error. R5 doesn’t have such problem, so wait for update of firmware on R5m2. Also I will try to update firmware for the lens as well. May be some changes in camera settings may help.

Re: EOS R5 Mark II and Rokinon 14mm problems

deebatman316 — Fri, 09 May 2025 14:33:56 GMT

This would happen with older 3rd Party EF lenses from the film era. The lens would draw too much power to stop down the aperture. This is likely what’s happening with your lens. Sometimes the camera will report the error or just lock up. So Rokinon will have to update the firmware for it to be compatible. Canon doesn’t know how 3rd Parties make their lenses work on their cameras. Instead it’s reverse engineered to work.

Re: EOS R5 Mark II and Rokinon 14mm problems

zailgan — Fri, 09 May 2025 14:40:29 GMT

How do explain that it works on R5 and doesn’t on R5m2. Lens is not so old :). Camera shouldn’t freeze, it’s professional device, it may show error but not freeze. There is incompatibility between lens and camera R5m2.

Re: EOS R5 Mark II and Rokinon 14mm problems

deebatman316 — Fri, 09 May 2025 14:55:44 GMT

Easy the same lens can work fine on an older camera but not a new one. Just like my example a family member upgraded from the EOS 10D to the EOS 40D. None of their old Sigma lenses would work on their new camera. Instead the camera would lock up or throw an error code. The lens wasn’t that old either. Canon DOES NOT tell 3rd Parties how their lens mount communication works. Instead it’s reversed engineered to make their lenses work which doesn’t always work. Canon can ensure forward and backward compatibility. A 3rd Party manufacturer cannot. I can use the very first EF lenses on my modern camera and have no issues. But yet a lens from a few years ago is incompatible. Same thing goes with flashes how can I use a 25 year old Canon 380EX. But yet a 3rd Party flash from a couple years ago doesn’t. It’s all reverse engineered so forward and backward compatibility IS NOT ensured.

Re: EOS R5 Mark II and Rokinon 14mm problems

Waddizzle — Fri, 09 May 2025 15:14:37 GMT

“ This Rokinon has manual focus but diaphragm is automatic. So it’s not fully manual lens. “

This thread is about the fully manual lens that is pictured below, then please start a new. The lens under discussion is fully manual with a focus confirmation chip. It also has a manual aperture control ring.

Re: EOS R5 Mark II and Rokinon 14mm problems

shawl — Fri, 09 May 2025 17:19:22 GMT

I have to respectfully disagree. The lens DOES automatically change f/stop when used in shutter priority mode. (I just test this on my 5d mark iv.)

Re: EOS R5 Mark II and Rokinon 14mm problems

shawl — Fri, 09 May 2025 17:20:44 GMT

I'm not seeing any firmware updates on the Rokinon site. 😰

Re: EOS R5 Mark II and Rokinon 14mm problems

shawl — Fri, 09 May 2025 17:25:34 GMT

I agree with all you say. Yes, the R5mii does lock-up...I again just tried it! There are no firmware upgrades on the Rokinon site I'm afraid.

Re: EOS R5 Mark II won't take a photo with a Rokinon 14mm lens

zailgan — Fri, 09 May 2025 20:00:41 GMT

I have two lenses Rokinon, first is fully manual lens 24 f1.4 and recently purchased 35 f1.4 with manual focus. Just checked first one and it works without any issues, but second one doesn’t. Also I found that focus confirmation works differently on them. May be this is problem, will try to play with settings. My plan to use them for Astro photography.

Re: EOS R5 Mark II won't take a photo with a Rokinon 14mm lens

Waddizzle — Sun, 11 May 2025 01:52:09 GMT

This lens is a fully manual lens. Just because it may display an aperture setting doesn’t mean that the camera is controlling aperture.

Rokunon does make a fully automatic 14mm lens, but this one is not it. It has an aperture control ring, something that is not normally used on Canon EF mount lenses with automatic aperture control.

Re: EOS R5 Mark II won't take a photo with a Rokinon 14mm lens

zailgan — Sun, 11 May 2025 13:41:00 GMT

Your photo is correct and I don’t see aperture control ring.

With AE chip

No AE chip

Second one without AE chip has aperture ring. My version even I have 35mm 1.4 looks like first one. Anyway I found a lot of complains in internet. It looks like Rokinon with AE chip lenses don’t work for newer EOS R cameras such as R6m2, R7, R5m2 and so on. But they work for R6, R5. Also there is no way to update firmware on Rokinon lenses and I don’t think Canon will do it to support third party lenses.