I知 thinking about adding the 90mm to my kit (already have the 35 and 65), but I知 worried about the AF when comparing to the 85 1.8. Is there a big difference? A few pages back someone compared the AF of these two and mentioned that the native 85 is faster and more precise. And that this also applies to the 35/2 vs 35/1.8. So what do I choose? Rendering or AF? I知 not a professional, I take photos of my travels and my kids. Kids are almost like BIF Good AF is important
Mzrk wrote:
I知 thinking about adding the 90mm to my kit (already have the 35 and 65), but I知 worried about the AF when comparing to the 85 1.8. Is there a big difference? A few pages back someone compared the AF of these two and mentioned that the native 85 is faster and more precise. And that this also applies to the 35/2 vs 35/1.8. So what do I choose? Rendering or AF? I知 not a professional, I take photos of my travels and my kids. Kids are almost like BIF Good AF is important
Don稚 let the technicalities of a couple of percentage points in AF Accuracy bother you, because in Sony vs. Sigma vs. Tamron, in this F/L range ALL the lenses are excellent in AF and way more accurate than in years past. It is just that the Sony G and GM are the most accurate with Moving subjects, with (typically) a couple of shots missed out of 100, whereas the Sigma may miss 4 or 5 and the Tamron may miss 6 or 7, they are that close. I have all 3 brands and for non-moving subjects they are all about equal in AF accuracy.
I have 5 of the Sigma I series lenses including the 90mm and it is excellent, just look at the 4 fall color photos above by @Peire, what more could you ask for? To me the rendering, IQ, handling, and feel of the lens is way more important than a few points in AF accuracy, as so many are in focus. BTW, I had the FE 85 f1.8 and after 8 months in 2019 I upgraded to a Batis 85 f1.8 for better rendering and results, could not be happier.
Mzrk wrote:
I知 thinking about adding the 90mm to my kit (already have the 35 and 65), but I知 worried about the AF when comparing to the 85 1.8. Is there a big difference? A few pages back someone compared the AF of these two and mentioned that the native 85 is faster and more precise. And that this also applies to the 35/2 vs 35/1.8. So what do I choose? Rendering or AF? I知 not a professional, I take photos of my travels and my kids. Kids are almost like BIF Good AF is important
You may be better off shooting kids one of more recent Sony zooms than the longer primes.
AF with the Sony FE 1.8/85 has been pretty unreliable for me for moving subjects especially wide-open. It is one of the lenses that supports 120 FPS AF-C tracking, so maybe it works better on the non-7 series bodies? I don't find the Samyang 85mm F1.4 AF to be worse. I haven't used the Sigma 90i enough in AF-C to give an opinion about its performance. It is low amount of breathing helps when focusing outside the center of the frame.
Mzrk wrote:
Thanks for the comments on AF. Do you know if the 90mm is a true 90mm? I know the Sony 85 1.8 is somewhere around 82mm.
The Sony 24-105 G reports 78 mm when I match the Sony FE 1.8/85 at preset infinity. It reports 89 mm for the 90i. The Sigma is also close to the Sony FE 2.8/90G at preset infinity.
The Sony FE 1.8/85 seems to have more focal length than the Sigma at MFD. They match at about 1.5 m focus distance.
Good AF is important