EF Lenses on R Mount (f/1.2 portrait primes)

CESA wrote:

Thanks for your comprehensive response. I have a canon 6D. Will do as you suggest in here. Will setup different targets at different distances and will also do the trick with the batteries.

I have an EOS 6D as well.  The test that I posted pictures of was made with that camera so I know you have a Micro Focus Adjustment option on your camera.  Something to consider it that after you have calibrated your camera for a specific lens is that if you change lenses several times, you may find that the AF needs a very slight re-calibration with the MFA setting.  It happened to me and it has also happened to another member here.  No idea how or why.

I think that you should be able to focus at any distance right? From minimum or say 1m up to whatever. I normally shoot at 1.5m up to 7m but sometimes like to do some at 1m.

At longer distances, the region that is in focus increased.  So if you do your test at around 5 or 6 feet from the camera to the AF targets, your eventual focus lock with the MFA ought to be fine with longer distances.  Don't be tempted to try the MFA adjustment without the camera resting securely on a tripod.  I tried making an adjustment in a shopping center one day and ended up making my focus worse.  I did it again when visiting family.  I just felt that the lens wasn't always hitting the focus all the time, even though I believe it was a very good copy.  This was the reason I gave it up to buy the RF version but a part of me does miss my EF lens. Your 6D can remember and store your MFA settings for up to 40 lenses and even 4 variants of the same lens.

I will take the time to do some assessment and follow your advice. Will come back with more.

If you own any f/1.2 (and possibly any f/1.4 lenses) that you use on your EOS 6D, you will probably need to do an MFA adjustment, even if you have a good copy of the lens.  Still, do the test with the Live View AF and the OVF AF and compare the results before you're tempted to touch anything.  The process is very easy to do should you require a calibration.  The MFA process stores the changes to your camera and has no effect on the lens itself (unlike the Sigma Lens Docks).  So if you sell your camera or lens later down the track, just erase the stored lens settings.