AF issues

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Fred Hummel

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Started having way too many soft focus images, actually out of focus. I've been doing this since 1969, owned studio for 20 years & never ran into something like this before.
Tested today as follows: set up with auto fine tune target level on tripod, camera(s) on tripod and nothing moved. Twenty foot distance, studio flash lighting eliminated movement issues.
#1 Nikon 850 with Nikon 70-200 and Nikon 200-500 both at wide open; and #2 850 with same lenses and technique. AF-S, ASA 64, 1/200. Used live view, pixel peeping for focus, set for back button. Tested 70,105, & 200mm; and 200, 300, & 500mm with each 850. Problem happens the same AF-S or AF-C.
Here's the issue: with both lenses on both cameras AF was clearly out of focus, worse on #1 850. Manual focus was acceptable. Neither camera has been used hard, all equipment is about 2-3 years old and (I presume) in fine condition.
Either I am doing something wrong, incorrectly setting cameras or both have an issue with AF.
I'd love to hear if anyone has had similar experiences, any corrective action, or just the forum's thoughts.

PS: I know someone will ask for pics but please accept that AF does not focus sharply without seeing a couple dozen images showing same.

Fred
 
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Did you complete the fine tune and re-tested the lenses in the field again.

Asking for a sample image is often the quickest way to get feedback because we can see something rather than trying to imagine it Details of settings used can also help to narrow things down.
 
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It is hard to believe you have 2 out of spec cameras and 2 out of spec lenses. To help with diagnosis you might try playing with focus peaking to see what the camera thinks is in focus. Set the camera on a tripod with remote release, Live View AF-S pin or normal focus and use the i button to enable focus peaking. #2 should do. With the camera and lens in AF mode let the camera auto focus, then without moving anything, especially the focus ring, go to MF on the lens and M focus on the camera and see what focus peaking thinks is in focus. I just tried it on my D850 and focus peaking showed a red border around the thing I focused on using Live View AF-S, just like it should and zooming in, my subject at the focus point was tack sharp.
 
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Thanks for the replies. VR turned "off" on each test. Both lenses have been fine tuned and used in the field for quite a while before this problem arose. The focus target is a Vello Lens Calibration set, and this problem is not limited to the target. I will try to send an AF and a M pic in the morning although they will only show out of focus (AF) and in focus (M) images. 70-200 set to A/m, 200-500 to M/a, both cameras set to AF.
All thoughts welcome and appreciated.
 
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Sorry about delay in responding, "my" time is not always my time.
Just finished blow out of focus sensors but what seems to be more important I also cleaned contacts & flanges on cameras and lenses.
Getting a much better response now, that may have been the issue.
Thoughts still welcome, thanks for replies
Fred
 
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