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p.2 #8 · p.2 #8 · Sigma Art and autofocus accuracy with Nikon? | |
ilnonno wrote:
I may be a cynical, but I wonder why people don't complain the same – or with similar energy – with regards to Nikon lenses... because honestly, even our highly treasured original Nikkors can have a hard time focusing, it just goes less public.
The 24 1.4G is a very, very hard lens to focus reliably, many find it so, my copy does it too. It's just the nature of the beast.
The 35 1.4G, when I had it, could be considered anything but a focusing champion, especially at a distance, no matter the af fine tune. Sold it when I acquired the ART, which simply is better and more reliably focusing (not by much, but still...).
The 85 1.4G, when I had it, was marred by serious focus shift between ƒ1.4 and ƒ2 onwards, visible even on 12mpixels bodies, which made it hard to fine tune it. Oh, and loved to misfocus too...
Then, the elephants in the room: the 2.8 pro zooms.
In a few years I owned 2 copies of the 24-70, 3 of the 70-200 VR II, and 2 of the 80-200 AFS. They all, to some extent, did show issues.
My best 70-200 VR II was spot on from 80+ to 200mm, and very sharp (even at the dreaded 135mm mark...), but unuseable (on 3 bodies) at 70-80mm, as there it required a completely opposite focus compensation (like +8 in the over 80mm range, -13 in the 70-80mm range; my current one shows less overall variation, but is also quite a bit less sharp, being quite poor between 105 and 135mm).
My 24-70afs both required different af-tune between 24mm and 70mm. So calibrate it for 24, or for 70, or accept a compromise and a bit of sharpness loss. The latter was better. Current 24-70 VR is better behaved, but I picked it out of 4 samples I tested, the other 3 of which did show this issue to varying degrees.
Yes, lots of people will tell "I've never seen/heard anything like this", but this is my experience with multiple bodies lenses, tested even with tripods. And I get to cherry pick my Nikkors in the shop.
Of course, Nikon equipment might just be allergic to me
So, how are my ARTs?
Sometimes they hit, sometimes they don't. Probably faring worse than the best Nikkors (my two best focusing lenses are the 105/1.4 and the 200/2, and even them are perfect 100% of the time), but in the same "acceptable enough" range (yes, I truly want CDAF...).
But there comes the USB dock: they can be fine tuned by distance, which is huge: many lenses, Nikkor included, require different fine tunes for distance, and the Sigma allow for this. It is amazing to see sharp pictures both far and near
I haven't tried the newest D5/500 autofocus, which is said to be better (still own D750/810), and am really curious to see if it brings more reliability for static focusing or not. Perhaps yes, as even the D810 improved things quite a bit vs D4/D800 which I had.
Sorry, just my rant.
The Sigma's are astounding lenses, both in terms of quality, or of quality/price ratio. I own 24/35/50 and 24-35, and while sometimes they give me headaches, they more often than not work as intended, and in many cases, better than the corresponding Nikkors. (I have no data on the newer 1.8G primes generation, which could be much better than the 1.4G).
Are they perfect? Not by a long shot. I've literally just taken the 35 Art and the D810 and shot a few frames (wanted to lend myself some credibility ). Of course, the first one was badly misfocused!
The others were more or less spot on, both far and near, both in house and outside. Live View focusing nets you better results relatively often though. That's just the nature of our autofocus system.
Perfect? no. Acceptable? I'd say yes... unless one is willing to switch to Sony for CDAF focus.
Sorry for the long rant...
Bests,
Lory...Show more →
I can only write from my own experience with a Sigma 35A on my D600. It could be alot better on the D800/E or D810. The 35A was my first 1.4 lens. I wanted the Nikon version but wanted to save some money. It was my 3rd copy I bought from Amazon. Amazon even told me if the 3rd copy was not good enough for me, they would not send me a 4th one. My first copy needed over +20AF adjustment. The second copy had a scratch on the front element so I didnt bother testing AF accuracy. Luckily the 3rd copy was ok and within range to be used with the USB dock but it still had inconsistent AF accuracy. Even worst when used with a Nikon flash. I did like the lens sharpness so I bought an A7R and a Nikon mount adapter to try to use the Sigma manually on the A7R. However, manual focus is much slower than AF especially when trying to nail focus at F1.4 so I gave up on the lens.
Last year, I have bought two Nikkon 1.4 lenses, 24G and 58G. To my surprise (I had thought I would never get good consistency shooting at f1.4) , both are much better in providing consistent results after AF adjustment. I did read about folks having issue with the 24G 1.4 during my time researching about the lens but I did not have a problem with it.
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