This afternoon I was trying to take pictures of small birds and my R5 with the RF100-500 mm lens would in certain situation focus out to infinity and then it was very difficult for it to refocus on a small close up subject (e.g. a Chickadee). This did not occur with all background, but appeared to occur more frequently when the background had high contrast and the foreground had less contrast.
If anyone has found a solution to this occurrence please share and thank you in advance.
Lighting and subjects all play a factor when you are shooting with autofocus.
AF mode tells the camera what to focus on and where emphasis should be placed
Examples can also include things like shooting from within a shaded area to a subject beyond in the sun, or shooting though bushes, branches, a window or fence.
It might be helpful if you provided a few examples with settings, maybe we will see something that stands out.
What has worked for me is to have dual bbf. One button for single point with auto servo, and one button for auto face reconition. I can then push the single point to get the lens to focus on the subject I want (useful when there are lots of background clutter or lots of birds) then switch to the other button to use face reconition and tracking. Seems to work every time. By the way using R5 and 100-500 also.