topic Re: EOS R only takes photos with MF prime lens in EOS DSLR & Mirrorless Cameras

EOS R only takes photos with MF prime lens

shuttermaus — Sat, 19 Apr 2025 15:42:11 GMT

Hello!

Wondering if this lovely community can give me some advice.

I have an EOS R that is on 1.8.0.

It has recently developed an issue where it will only take a photograph with my manual lens that I have.

I have cleaned all the contacts.

I have battery reset it.

I have reset all the settings.

Cleaned the sensor.

I have EF and RF Mount lenses.

Neither direct contact or contact with an adapter seems to make a difference

The screen flashes multiple times and I can hear the focus drive working on each lens as it's connected, like it's trying to focus.

This happens no matter what mode I am in.

The only lens that seem to be not affected by this is my fully manual fixed 90 prime.

The only thing I can think right now that it is a pin that affects the drive is messed up

Thoughts?

Re: EOS R Focusing Issue

deebatman316 — Sat, 19 Apr 2025 15:30:01 GMT

What is the ambient lighting like is it low. Is there plenty of contrast if not the camera won't focus. If the ambient lighting is low the camera may temporarily increase the ISO to help with AF. What is the AF mode set to One Shot, Servo AF or AI Focus. In One Shot if the camera can't lock focus the LED AF Assist Beam on the camera body will emit an LED AF Assist Beam. If a Canon Speedlite is being used the IR AF Assist Beam WILL NOT FIRE instead. Instead the Speedlite will switch to Intermittent Flash Firing to aid the camera's AF system and that may allow the camera to lock focus in difficult lighting. The AF Assist Beam type projected is Dependent ON THE AMBIENT LIGHTING. What lenses are you using please provide the full name and if you're using a mount adapter. Is it a Canon brand mount adapter or a 3rd Party Mount adapter those are nothing but trouble.

Re: EOS R Focusing Issue

shuttermaus — Sat, 19 Apr 2025 15:37:33 GMT

This happens regardless of lighting or settings.

This happens on every lens or adapter I use.

I can get the lenses to fire on manual focus which then prompts an err 01 which prompts me to check connections which leads me to believe it's one of the pins

Re: EOS R Focusing Issue

deebatman316 — Sat, 19 Apr 2025 15:40:48 GMT

Does this happen with all lenses. What are the Full Names of the lenses being used in question and the mount adapter if used. Stick with the Canon brand Mount adapter. 3rd Party Mount Adapters are nothing but trouble. Without knowing the lenses you're using we can't help you especially without complete names. Have you tried using the lenses on another camera to see if they work.

Re: EOS R Focusing Issue

shuttermaus — Sat, 19 Apr 2025 15:47:51 GMT

This happens with all lenses.

I've used

18-150

Sigma 150-500

Canon ef to rf adapter

RF 55-210

RF 85

All ef lenses work fine on my canon 70d

Re: EOS R only takes photos with MF prime lens

shadowsports — Sat, 19 Apr 2025 15:57:51 GMT

Greetings,

Based on your responses and activities performed, it sounds like it's time for the camera to visit a Canon repair facility.

Re: EOS R Focusing Issue

deebatman316 — Sat, 19 Apr 2025 15:59:07 GMT

Ok 50mm what it should say for example EF 50mm F/1.8 STM. Those names you've listed are incomplete some of those lenses have multiple versions. Which EF-RF Mount Adapter Canon has made 3 different versions of that mount adapter. The basic one, Control Ring, Drop in Filter. Do you own a Canon Speedlite/ External Flash that you can try on camera. Any Canon EX series or EL-1 & EL-100 will work. It looks like you have some RF-S lenses too which won't allow the camera to use the entire sensor area. Instead its cropped to the APS-C image field greatly reducing megapixels. In APS-C mode its only 11.6 megapixels instead of the 30 megapixels the camera can use.