RF 24-105 L Manual Focus Issue

[msmith66]

Hello - I am experiencing an issue with manually focusing my RF24-105 lens.  I have an R6 set up for triple back button focus with no focusing on the shutter button.  The lens focuses fine in AF and if I switch the lens to MF it focuses fine as well.  However, in AF, if I move the focus ring without having a back button pressed, the lens does not manually focus.  I have been over and over my settings and cannot find anything that will change this behavior.  If I attach my RF 100-500, it manually focuses as expected with the focus ring.  The 24-105 L is on firmware 2.0.6 and the camera is on 1.7.0.  Electronic full-time MF in AF5 is set to ON.  Does anyone have any ideas or suggestions?

Thanks!

[stevet1]

It may be lens-specific.

What does your lens manual say?

Steve Thomas

[deebatman316]

All RF lenses wether STM or USM are focus by wire. You must press and hold the AF-ON (or whatever button is set to enable Focusing) for manual focus to work.

[msmith66]

I appreciate your response but this is not my experience.  My RF 100-500 manually focuses anytime you move the ring without any AF button being pressed.  I use it all the time like this and have since I purchased it.  And, the RF24-105 L does not manually focus, regardless if a focus button is being pressed or not.  I have tested this every way I can think of and it just doesn't manually focus unless the switch on the lens is on MF.

[deebatman316]

Manual Focus override doesn't work in AI Servo. Make sure the camera is set to one shot and retest. Also make sure Manual Focus after One Shot AF is Enabled. IF NOT Manual Focus override won't work at all. The default function for this behavior is disabled. This is from the EOS R5 but this custom function applies to the R6 too check this custom function.

[msmith66 · Accepted solution]

I've resolved this myself and will provide some information here in case anyone else runs into this problem. 

First off - my camera is in Servo AF and always in servo.  I have no use for it in One Shot.  I would never intentionally put it in One Shot for any reason.  So, everything I reference here is with AF1 --> AF operation = SERVO AF.  I read your post above after I had figured this out  but this setting on my camera was AF4 --> Lens electronic MF = Disable in AF mode.  As mentioned earlier AF5 --> Electronic full-time MF = ON.  (a note - if its off the focus rings do not work at all).  The AF|MF switch on the lenses is set to AF and the focus trigger is set to back button Eye AF and metering start only on the shutter button half press. 

So here's the thing - with the AF4 --> Lens electronic MF = Disable in AF mode, the RF 100-500 will still manual focus without the AF triggered, at any time.  Even immediately after powering the camera up.  The RF 100-500 seems to ignore the Lens electronic MF setting in AF4.  I use the RF 100-500 95% of the time with this camera and its just always worked the way I want - at will manual focus.  

The RF 24-105 L does care about the AF4 --> Lens electronic MF setting and it can be set to One-Shot --> enabled or One-Shot --> enabled (magnify) and it will manual focus at will, regardless of any button presses or holding the shutter down, just like the RF 100-500.  If the setting is Disable after One-Shot or Disable in AF mode, it will not focus with the ring regardless of AF activation or button presses.  I have verified that these settings also work with the RF 100-500 and I cannot find a difference in the way either of these settings work.  What Canon has written in their documentation (p. 417 of the manual) for these settings is just plain confusing and inaccurate.  It has nothing to do with One-shot AF.  I have a feeling it is a holdover from earlier DSLR models and doesn't apply to newer RF lenses or bodies.  Why the one cares and the other doesn't I'll never know but I have it working the way I expect now. 

Thanks - hopefully this helps someone in the future.

Edit on 3/2/24 - I recently acquired an R5 and was again having trouble getting the manual focus ring to work as it did on the R6.  I realized that when I set BBF up I did not take AF on off of the shutter button.  This will not let the manual focus ring work.  After setting it to meter start, it works fine with the above setting.