Sigma 56 F1.4 on M6II versus RF 85 F2 on R

thunder storm wrote:

Alastair Norcross wrote:

I've never experienced anything like that with the RF 85 on my R. Do you think it's peculiar to the R5?

It's mainly with AF face/eye tracking at speeds and/or in situations needing "stickyness" the R can't handle anyway. Now that might seem challenging, but my Sigma lenses don't have these kind of problems on the R5, while these are third party lenses in stead of OEM brand native RF. It seems somehow AF speed is prioritized over stickyness to the subject. Now there isn't a whole lot of speed to trade here, however, I do prefer stickyness to be main priority, and speed the secondary. Or, even better, gimme a setting to tweak these things.

Can't you tweak them in camera?

The low light jumping though was the same on the R. With low light the AF can jump even with moderate movements.

When using the IS at full extent there's not a whole lot of light as the IS is very good, and then it even doesn't take any movement to get hunting AF. Still, my EF 24-70mm f/2.8 mkII doesn't hunt in the exact same situations (on a tripod), while it is actually a stop slower and isn't a native RF lens.

It's possible I haven't used it in those situations. Probably the lowest light I used it in for moving subjects was stage lighting, taking rehearsal shots. It had no problem sticking to the eyes of moving actors, in lighting that varied quite a bit (it was a rehearsal, so the lights were all over the place). Otherwise, I've used it for fast runners in good light, with no problems.