Another focus issue

[Ted Evans]

Trying to fine tune my lens and camera's AF. Here is what I have so far.

Tamron 150-600 - +16
Nikon 18-140 - + 18
Nikon 200 f/4 micro - +16

Nikon 80-200 f/2.8 D - cannot get it even close, very strong back focus. A -20 setting results in back focus 2-5 as being the sharpest. A +20 results in 5-7 being the sharpest. If I manually focus, 0-2 front focus is sharpest. It seems to me there would be more separation from +20 to -20 but I have run the test three times and the results are always very close.

Does this mean that the lens is so far out that it will have to go to Nikon? Although the lens is from the early nineties, it has been used very little and usually on a tripod above f8. Is there another option?

Thanks for your comments.

 

[Ted Evans]

Trying to fine tune my lens and camera's AF. Here is what I have so far.

Tamron 150-600 - +16
Nikon 18-140 - + 18
Nikon 200 f/4 micro - +16

Nikon 80-200 f/2.8 D - cannot get it even close, very strong back focus. A -20 setting results in back focus 2-5 as being the sharpest. A +20 results in 5-7 being the sharpest. If I manually focus, 0-2 front focus is sharpest. It seems to me there would be more separation from +20 to -20 but I have run the test three times and the results are always very close.

Does this mean that the lens is so far out that it will have to go to Nikon? Although the lens is from the early nineties, it has been used very little and usually on a tripod above f8. Is there another option?

Thanks for your comments.

An update.....just received a Tamron 70-200 f/2.8 and the focus was almost dead on. I tried the 80-200 on my old D200 and it was very close. Apparently, the combination of lens and camera can make a difference in the focusing. Thanks to the folks that comment in this forum, I was not aware of the lens alignment issue until reading it here.