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+--- Thread: Preview: Fujinon XF 23mm f/2 R WR (/showthread.php?tid=258)
Preview: Fujinon XF 23mm f/2 R WR - Brightcolours - 06-22-2017
Just that with a lens that lets in less light, it becomes noticable that the camera is slower in focussing.
Preview: Fujinon XF 23mm f/2 R WR - JJ_SO - 06-22-2017
Quote:What has slow focus in the dark to do with the lens? We don't do camera tests ...
I know. But lenses are used exclusively with cameras and never alone, and if a certain lens forces the camera to switch to a slower AF-mode, the lens HAS to do something with AF. This means the APD version of the otherwise not too bad focusing 56/1.2
To me it was very strange to see the AF of the 50/2 nearly creeping to focus. I would love to do a comparison in similar light situations, but as I said, the 56/1.5 APD takes a stop at the service boxes of Fuji. Rattle-rattle-rattle...
![[Image: drums36x28.gif]](http://www.macinacs.de/smile/drums36x28.gif)
a very rythmical lens in the right hands.Preview: Fujinon XF 23mm f/2 R WR - Klaus - 06-22-2017
Quote:Just that with a lens that lets in less light, it becomes noticable that the camera is slower in focussing.
The mirrorless AF (both PD- and CD-AF) slows down due to increased sensor noise in low light. Which increased sensor noise the readings become less accurate thus the camera has to take more readings to compensate that.
Preview: Fujinon XF 23mm f/2 R WR - JJ_SO - 06-22-2017
Additionally, in AF-C mode the camera worses things by stopping down the aperture - so, no matter how fast the lens could be, it is set to working aperture.
Mine was wide open, in AF-S and slower as I ever had it on the old Sigma Merrills.