I use C1-C3 mode (manual modes with slightly different AF parameters, auto update disabled), primarily C3 because it is adjacent to the video mode. Every now and then I notice these 2 issues:
First is that the aperture is sometimes remembered as the narrowest one at the long end of my lens (for example f9 for the 200-800mm or f8 for the 100-400mm). This issue didn't bother me much back when I was regularly using the 800mm f11 but I have noticed it more when using the 200-800mm as my daily driver. I sometimes end up forgetting to make sure it is wide open at the wider end and it ends up shooting at the narrower apertures. I find that setting the lock button as the widest aperture (zoom out to 200mm and press lock when dialed back to f6.3) does help keep proper scaling, but only while I am using the lens. When I add the 1.4x extender and remove it, it sometimes gets locked at f13 or f9. I think the other thing that triggers the change is when I change to video mode and back.
Another issue I've noticed is that eye detection seems to get disabled for some unknown reason. I guess this has to do with filming in video mode with an AF mode other than object detection, but I'm not sure how I can ensure it always remains enabled.
First is that the aperture is sometimes remembered as the narrowest one at the long end of my lens (for example f9 for the 200-800mm or f8 for the 100-400mm). This issue didn't bother me much back when I was regularly using the 800mm f11 but I have noticed it more when using the 200-800mm as my daily driver. I sometimes end up forgetting to make sure it is wide open at the wider end and it ends up shooting at the narrower apertures. I find that setting the lock button as the widest aperture (zoom out to 200mm and press lock when dialed back to f6.3) does help keep proper scaling, but only while I am using the lens. When I add the 1.4x extender and remove it, it sometimes gets locked at f13 or f9. I think the other thing that triggers the change is when I change to video mode and back.
Another issue I've noticed is that eye detection seems to get disabled for some unknown reason. I guess this has to do with filming in video mode with an AF mode other than object detection, but I'm not sure how I can ensure it always remains enabled.