Has anyone had a Samyang/Rokinon lens that just quit autofocussing all of a sudden? I was using the Samyang 135/1.8 at an event and it went from autofucussing fine to not being able to focus at all while I was shooting with it in either video or stills. I don’t think it’s a firmware incompatibility or anything because the change happened mid-shoot rather than after I updated anything. If you’ve had that happen, did you find a fix?
I just had this happen with my SY50AFII over the weekend when mounted on the A1ii. (Don't laugh - I don't like shooting 50mm and purposely cheaped out on buying 50mm lenses).
Anyway, I was using a CPL in broad daylight and the lens and camera were hunting like crazy in AF-C mode on barely moving subjects. Although I have only had the A1ii for a couple of months, I've used it with a few of my Sony primes, and it focused quickly and confidently in substantially worse lighting situations.
Interestingly, I turned my CPL 1/4 turn and voilà! The Samyang locked and tracked focus in AF-C and pixel peeping photos taken at f/1.4, it nailed focus every single time.
Not sure if that was your issue or not. I have also tried to focus slowly moving subjects with the A9iii and this lens and it completely failed. I reshot the same situation with the ZA55 and same body and had no issues, so I suppose I would call the Samyang's AF capable "barely passable" at best. But again, I don't like shooting 50ish, so I knew the tradeoff up front on saving money.
I bought this exact lens a few months ago to try alongside Sigma 85. It was an excellent lens but AF did not work in one of the focus modes, I forgot which one. It needed a firmware upgrade to address, explicitly mentioned on their site for my camera - A7V, which was very new at the time. I ended up keeping 85 so didn't need to follow through with the upgrade. Google for "samyang 135mm f1 8 af software version 6", or try this directly:
"Version 6
Date 2026-01-19
Details Improved Operational Stability with the Sony α7 V(a7M5)
- Enhanced stability and reliability for AF-S mode and overall lens operation"
Thanks for the suggestions everyone, I’ll look into the firmware and other settings. Maybe I accidentally hit the switch too…
I also have the 50 1.4 ii, and the tiny 45 and 75. I’ll need to test them as well, hopefully they still focus on command. It’s never been an issue before