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05-04-2021, 05:40 AM   #16
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QuoteOriginally posted by niels hansen Quote
I understand you are confused. My explanation was not overly precise.
On tripod I make a pdaf pose on 2,8, the result is OK, the same as with cdaf. If I make a pose on 5.6 with pdaf the result is blurry. If I let the pdaf work on 2,8 and then switch to MF, stop down to 5,6 and dont touch the distance scale, then the result is good. My conclusion is that pdaf communication between camera and lens lens is ok on 2,8, but is bad at 5.6. The MF setting removes the bad lens - camera communication, therefore the sharp result
regards

---------- Post added 04-30-21 at 03:12 AM ----------


thanks
The Sigma is screw driven
To be honest: I am afraid of updating. I have read that mistakes the camera get off. One of the things I am afraid of is the battery. It must be fully loaded, but I dont know the condition of my batteries. My third party battries are cheap crap., the KP was bought in 2017, the delivered battery is from 2015, My feeling is that the capacity no more is 100%. Is there an objective test I can make with a multimeter instead of "kitchen tests"
My best update solution may be to drive the long way to Copehagen and pay the dealer.
I have succeded with making troubles out of many easy installations, therefore I am afraid
This might be a stupid question, but where do you change the aperture setting from? That Sigma lens is equiped with an aperture ring that can be used to change settings independent of camera settings. This is not the best way to use the lens and I do not know if this has any effect on focus, but it's the only thing I can think of at the moment.

05-04-2021, 05:48 AM   #17
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We are not talking about the same lens, it is a Sigma 70mm 2,8 DG MACRO without an aperture ring ( by the way I miss an aperture ring on almost all of my digital lenses)
05-04-2021, 05:48 PM   #18
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A couple of other things...

1) are you using the timer delay to fire the camera or just pushing the button? After your adventure with the timer at the top of your thread, I get not wanting to go through that again, but it does make a difference, and it disables the SR when you're on the tripod. Your shutter speed at f5.6 is 1/3s, which is slow at 70mm handheld (or on a tripod without the timer)

2) Have you tried adjusting the aperture with the focus locked and in AF? Focus using single shot PDAF at f2.8. Without letting up on the shutter button, adjust the aperture to f5.6. Then take the shot. The focus should not move since it already confirmed...

-Eric
05-04-2021, 07:07 PM   #19
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It is on tripod and 2 sec delay. I always use single point af.If I focus on 2,8 in PDAF and then turn the aperture to 5,6 the pose is sharp. The blur comes when focusing in 5,6 and PDAF. The attached photos shom that at 5,6 the front focus is significant. The 4 way controller works

05-05-2021, 12:10 AM   #20
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QuoteOriginally posted by niels hansen Quote
It is on tripod and 2 sec delay. I always use single point af.If I focus on 2,8 in PDAF and then turn the aperture to 5,6 the pose is sharp. The blur comes when focusing in 5,6 and PDAF. The attached photos shom that at 5,6 the front focus is significant. The 4 way controller works
Did you buy the lens new or used? I have read somewhere that with the Sigma dock (i do not know if they are compatible) you can tune parameters related to focus fine adjustment. I am just throwing it out there as i have no experience with the sigma dock.
05-05-2021, 12:50 AM   #21
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It was bought new in 2012 , worked and works good on K 30, the KP is bought new in 2017. the issues have appeared a month ago. The attached photo is exellent in A4 and A 3 prints. Hope the rendering is good enough. What is Sigma dock??
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K-30  Photo 
05-05-2021, 10:33 PM   #22
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QuoteOriginally posted by niels hansen Quote
It was bought new in 2012 , worked and works good on K 30, the KP is bought new in 2017. the issues have appeared a month ago. The attached photo is exellent in A4 and A 3 prints. Hope the rendering is good enough. What is Sigma dock??
This is the USB-dock: Sigma USB Dock | SIGMA America
I bought it together with the Sigma 17-70mm f/2.8-4 but have never used it. Your lens is probably to "old" to work with the dock - at least it's not listed.

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