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09-16-2016, 12:21 PM   #1
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Sigma 85mm 1.4 and K5II

Hi Guys !

Did any of you use that lense with the K5II ? i got hard time to calibrate the AF fine adjustment.
For close subject i have to set it -7 to have something sharp and for far subject i have to set it 0
did other like me got the same problem ?

09-16-2016, 12:32 PM   #2
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Think it could just be the shallow DoF? It's not easy to always nail the focus, and if you don't need a calibration at longer distances, applying some might backfire.

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09-16-2016, 12:42 PM   #3
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well i'm using a tripod with a Af adjustement chart. My adjustment is set for 1 meter at this distance the dof is really shallow but i got something sharp at -7. at 0 it's completly out of focus (front focus)
but i want my lense set for close and far subjet
09-16-2016, 01:19 PM   #4
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if you read through the reviews of the lens on here you will see there is at least one (maybe two people) who mentioned that same exact problem with the lens. inconsistent AF based on the distance to subject. i am not sure if it is a lens specific issue or how wide spread it is :/

09-18-2016, 08:22 AM   #5
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Damn it !
thank for the reply guys, i'll check with sigma support if they can do something like upgrading the firmware.
09-18-2016, 11:37 AM   #6
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I don't have the 85 but the 50 1,4 and the fine tuning i set for what I use most but for close-ups I always have to make manual adjustments
09-19-2016, 02:09 AM   #7
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Hi Bengan,
This what i'm actually doing but i found this unacceptable from Sigma, this lense coast nearly 900$. i expect a service for the price.
09-19-2016, 02:27 AM   #8
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QuoteOriginally posted by B3rty Quote
For close subject i have to set it -7 to have something sharp and for far subject i have to set it 0
This is actually pretty typical for lenses with rear focusing groups, Over the past decade or so manufacturers have designed their AF 85mm lenses to be optimized for distances around 1.5~3.5M - those that are commonly subject distances for portraiture, rather than infinity or MFD. It is simply the nature of the beast.

09-19-2016, 02:34 AM   #9
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In short: I'm experiencing the same thing.... kind of.

I got mine the other day, but I'm using it with K-3 II. I did the first bunch of shots indoor in low light and up to around 3m distances, and first impression was overwhelmingly good - after I had fine adjusted AF to -5.

During the day I did some outdoor shots over longer distances, and the AF accuracy almost caused a panic. At 5+ meters it wasn't being too accurate. AF fine adjustment set to +7 did the trick, but I was still concerned, be cause I know I won't be fine tuning AF as I shoot.

Last night I went out to get me some cigarettes and brought the camera with me. It did better, much better, I'd say. I was out during the night so there were few flukes here and there but overall I got to the happy end of the scale again.

Today I did few more shots during the day, with AF fine adjustment still at -5 and it's performing better. So much so that I'm now thinking I wont even send it back or have it calibrated - buuuut, I wont judge too quick and I need to do proper "real world" scenario shooting. Have a wedding coming up next Saturday and plan on using this lens as one of my 2 main lenses.

My question about this is, is this kind of thing normal? As if a lens needs to break-in?

---------- Post added 19-09-16 at 11:36 ----------

QuoteOriginally posted by Digitalis Quote
This is actually pretty typical for lenses with rear focusing groups.
Meh, even though it may be somewhat "calming" to know this is normal, it's not very satisfying
09-19-2016, 02:38 AM   #10
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QuoteOriginally posted by Zafar Iqbal Quote
My question about this is, is this kind of thing normal?
yes, I work with the Sigma 85mm f/1.4 in Nikon F and Nikkor 85mm f/1.4G and I also use the Canon 85mm f/1.2L - All three lenses show focus shift to varying degrees.

The only portrait lenses lenses I own that show minimal* focus shift at different focus distances are: Zeiss Otus 85mm f/1.4,Canon 85mm f/1.8** Leica APO-Tele-Elmar-S 180mm f/3.5, Leica APO-Summarit-S 120mm f/2.5, The Pentax A* 85mm f/1.4, Contax Planar T* 85mm f/1.2, Pentax FA77mm f/1.8 Limited.

* But still show detectable amounts of it on an optics bench.
**Seriously, that lens should be designated as an L lens: it is very good for the price.

Last edited by Digitalis; 09-19-2016 at 02:46 AM.
09-19-2016, 02:48 AM   #11
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Mmmmkay. In case I feel the variation is too much, like going from -5 to +7, do you think there would be any chance of getting it improved by sending it in for a check-up?
09-19-2016, 02:55 AM   #12
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QuoteOriginally posted by Zafar Iqbal Quote
I feel the variation is too much, like going from -5 to +7, do you think there would be any chance of getting it improved by sending it in for a check-up?
Possibly, it could also be your particular camera body ( lens mounts aren't perfectly flat and can bend and wear over time) Unless you have a pressing assignment I can't see how an expertly done calibration to your particular camera body would hurt - but this is an inherent characteristic of the lens, you won't ever eliminate it entirely...and if you switch camera bodies often the lens might behave differently, due to the new set of variables behind it.
09-19-2016, 04:31 AM   #13
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I just tried it on my second body and to me the lens is performing the same.

I also compared it against 70mm Limited and Sigma 70-200mm Macro. It's a bit though to compare, because the smaller apertures on those lenses allow for a greater deviation in focusing inaccuracy, whereas the 85 wont allow it and slaps me hard.

The 70-200mm seemed to perform better but it's also the lens with the smallest aperture. Overall I'd say they are pretty much equal, judging from the few and very unscientific shots I did. In the end, real life usage matters the most and in real life scenarios, the 70-200mm often fails. Of the three, it is the most sluggish lens too though.

I also whipped out DA 50mm f1.8 to put things in perspective. Even though it's not a pro lens and even though I know it sucks big time, I've been using it a lot for especially indoor candid shots - but just for the kicks, I did some comparison shots with it as well. Of the 15 or so shots I did, 3 were in focus and the rest too much off. With some shots it's as if the lens just gave up and decided to plant the focus midair. Overall, it was just as expected but - much much much worse than the 85mm - and that is very good news.
09-19-2016, 06:06 AM   #14
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QuoteOriginally posted by B3rty Quote
Hi Guys !

Did any of you use that lense with the K5II ? i got hard time to calibrate the AF fine adjustment.
For close subject i have to set it -7 to have something sharp and for far subject i have to set it 0
did other like me got the same problem ?
My Sigma 85mm F/1.4 has been my most accurate lens on my K-5, K-3, & K-1. I don't think I have needed to apply AF micro adjust on any of them. I would send it back to Sigma for to have it adjusted. They did wonders with my 50mm F/1.4.
09-20-2016, 09:10 AM   #15
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Hi Guys,

I've decide to send the sigma to the dealer since i got 3 years warranty.
i'll tell you if the focus shift problem has been fix or not.
for the one who dont get the problem, i have to say you're the lucky one
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