honestly i'd skip the Sony FE 85mm f/1.4 GM. it’s kinda slow and unfortunately struggles to keep up with that a1 sensor... i had issues with focus missing. here is what i recommend instead:
- Sony FE 135mm f/1.8 GM: *literally* instant AF
- Sony FE 50mm f/1.2 GM: highkey better resolution for ur sensor the 85 is just not as good as expected. gl!

Ok so, been thinking about your question. For your situation, I would suggest being a bit careful with the Sony FE 85mm f/1.4 GM. It's honestly a bit of an older design, and while the bokeh is gorgeous, those AF motors aren't really built to keep up with the 30fps burst or the ultra-fast tracking on the Sony a1 Mirrorless Camera. Here's what I recommend based on technical performance: 1. Sony FE 135mm f/1.8 GM: This lens is basically a beast. It uses XD linear motors so the Eye AF is actually instant. Seriously sharp too.
2. Sony FE 50mm f/1.2 GM: If you want to maximize that 50MP sensor, this is it. It's lowkey one of the sharpest lenses Sony has ever made. I guess if speed and accuracy are your top priorities, the 135mm is definitely the winner over the 85mm GM. But yeah, make sure to check the weight cuz that 135mm is heavy lol. Good luck!

Coming back to this, seconding the recommendation above! Honestly, ur a1 is way too fast for that old 85mm GM. If ur looking for AMAZING value, check these: • Sigma 85mm f/1.4 DG DN Art for Sony E: Way faster AF and super sharp for way less cash!
• Sony FE 85mm f/1.8: Lowkey a beast for the price, reallyyy snappy motors. Basically, dont waste that sensor on slow AF motors. cheers!

Tbh everyone here is spot on—that old 85mm GM is basically the "bottleneck" for an a1. If you're looking at the market right now, Sony is clearly pivoting toward those XD linear motors in all their new stuff because the old screw-drive style just can't keep up anymore. Quick tips for ur kit:
* Consider the Sony FE 50mm f/1.4 GM: It's way more recent than the f/1.2 and honestly hits a sweet spot for weight/price while still being super fast for that a1 tracking.
* Check out the Samyang AF 85mm f/1.4 FE II: If you don't mind going third-party, their Mark II is surprisingly snappy compared to their first gen stuff, though maybe not "GM" level speed. Personally, I’d keep an eye on the rumor mills because a version II of the 85mm GM has to be coming soonish (at least thats what I'm hoping for haha). But for now, that 50mm f/1.4 or the 135mm are the safest bets for that sensor. Hope that helps!

Good to know!