I use One Shot + Single Shot for landscapes and street/travel, and Servo for wildlife.
Because I don’t use back button focus, One Shot is convenient for me to use focus-and-recompose. If it’s a small enough recomposition to not affect the focus, this can be quicker and more convenient than moving the focus point. Otherwise, if I used Servo, I’d have to press AF Stop (which I have mapped to the AF START and lens buttons). Obviously such a slight recomposition is a convenience on the R3 with its many focus points rather than the necessity it was on a DSLR with its sparse points. But I do still use that DSLR, quite often, and habits die hard.
Also, if my framing were to wobble, in One Shot focus would still be correct with just the composition a bit out, but in Servo the shot could be ruined with the focus slipping onto something at a different distance.
I have a custom mode for wildlife which turns on Servo, high frame rate, animal subject detection and evaluative metering all at once.
As others have stated, if using the AF-ON (Back-Button) with IA Servo, when holding the button down as you would with moving subjects it works as IA-Servo should, but when you focus on a still subject and release it, it locks focus just as in One-Shot.
Ferrophot wrote:
We all use what we are comfortable with. Back in the 7D days I found AI Servo next to useless so went to one shot centre point AF off the back button. I had the lens adjusted for very slight front focus and found that worked well for birds and moving subjects. Now with the R6 the huge improvements in AF mean that I use servo AF for everything off the shutter button set to low speed continuous.. Still use the mechanical shutter.
7D AF was always dicey. The missed shots were at a significant level even with AF microadjustment.
Ferrophot wrote:
We all use what we are comfortable with. Back in the 7D days I found AI Servo next to useless so went to one shot centre point AF off the back button. I had the lens adjusted for very slight front focus and found that worked well for birds and moving subjects. Now with the R6 the huge improvements in AF mean that I use servo AF for everything off the shutter button set to low speed continuous.. Still use the mechanical shutter.
I had high hopes for the 7DII as a cropped 'reach' camera for putting more pixels on distant subjects in some sports situations, but found the Servo AF so inconsistent, as well as acquisition lag, compared to the 1DX, that I couldn't live with it.
We are very fortunate now with the current selection of mirrorless cameras that are generally much closer in performance across the mid to high end pricing range. At least for me it's no longer necessary to have a 1 series (or equivalent) camera to do the same work that in the DSLR era necessitated those cameras. My initial transition to mirrorless was from the 1DXII to the R6II and my 'technically acceptable' keeper rate increased considerably. The R5II has improved on that even more.
