EOS R7 When does the manual focus guide frame appear and when doesn't it?

[givoly]

I love the ability to focus with the guide frame. As described here: https://cam.start.canon/en/C005/manual/html/UG-05_AF-Drive_0100.html

However, it works for me in a few lenses, but not in others. I cannot figure out what's the rule. And I want this utility whenever I'm focusing manually. So here's what I've seen:

It works with: Canon 70-200 f/4. Canon 50mm f/1.8, LAOWA 100mm f/2.8 (most useful, as this is a purely manual lens) - all connected with Canon's EF lens adapter to R mount.

It does not work with: TTartisans 25mm f/2 (connected directly to R mount), and another manual 135mm f/2.8 lens (via EF lens adapter) that I have. Both of these are manual lenses, and even used wide open - unclear why the guide frame doesn't appear.

Any idea on how to make it always work?

Thanks!

[shadowsports]

Greetings givoly,

A lens's ability to communicate with the body is only guaranteed with OEM glass. Some manual focus lenses might work, while others will not. There is no definitive guide for this since the lenses were not manufactured by Canon. Its going to be hit or miss, with some of your MF lenses working, and others not.

[amfoto1]

I have no idea why the guide frame won't work with those particular lenses.

Have you tried using focus peaking, as an alternative?

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
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