Focus test for MikeD7000

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Rick M

Senior Member
Mike is experiencing DoF shift on his 70-200 f4. As a test my results are as follows, 200mm about 4 feet at f4, 5.6, 8 and 11. Focus point surrounding the "12". I'm satisfied that my copy is maintaining about 1/3 DoF in front of the focus point on all settings. Mike, please add your results to this thread and we can compare. Perhaps a few other members might join in.


DSC_0062_12053.JPG


DSC_0063_12054.JPG


DSC_0064_12055.JPG


DSC_0065_12056.JPG
 
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MikeD7000

Senior Member
Thank you Rick. Before sending my lens to Nikon service I have focus at 200mm f4 just like you, but f5.6, f8, f11 were backfocusing so I could not get subject at close up shots in focus.
Nikon service calibrated my lens at 200mm with moving focus forward. Now you can see a little of front focus at f4 (focus point is at number 0). That also moved focus of other apertures (at 200mm) forward, so number 0 is now just barely in focus (or not entirely). Can you please give me your opinion comparing your and my pictures. Thank you.

200mm f4.0DSC_3493.jpg

200mm f5.6DSC_3496.jpg

200mm f8.0DSC_3497.jpg

200mm f11DSC_3498.jpg
 
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Rick M

Senior Member
I think i would now try fine tuning the body to lens at f4. Get it to 1/3 in front and 2/3 behind. If it does not remain consistent across the other apertures i would send it back again.
 
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MikeD7000

Senior Member
I understand what you mean, but the problem is I can't do that. If I fine tune at 200mm f4 to get 1/3 in front and 2/3 behind, then I have to put focus a little bit back. But if I do that then I move focus also at f5.6, f8, f11 a little bit back and number 0 won't be in focus. And in that case I get exact settings which I have originally before sending lens to Nikon service. I guess that is a defective lens or what.
 
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Rick M

Senior Member
MikeD7000 said:
I understand what you mean, but the problem is I can't do that. If I fine tune at 200mm f4 to get 1/3 in front and 2/3 behind, then I have to put focus a little bit back. But if I do that then I move focus also at f5.6, f8, f11 a little bit back and number 0 won't be in focus. And in that case I get exact settings which I have originally before sending lens to Nikon service. I guess that is a defective lens or what.
Click to expand...

If you can not achieve balanced results than yes, in my opinion it is defective. Especially comparing to my results, it is not a physical property at fault. It is the mechanics of your particular copy creating the variance.
 
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