mwsilvers Loc: Central New Jersey

For the Canon 7D Mark II, which both the OP and I own, there is a single adjustment setting for prime lenses and two settings for zooms, one at the wide end and and one at the long end.

mwsilvers Loc: Central New Jersey

Another option is to first use the in-camera adjustments to obtain the best compromise you can at the long and wide end which will also extrapolate towards the middle. Then use the Tap-in to make fine adjustments for any remaining AF issues. It's a bit of a compromise, but it takes much less effort.

knelso4

One way to speed this up is to put a narrow strip of white tape on the focus ring, focus with live view zoomed, turn off live view, and half press to focus through the view finder. Note the direction the focus ring moves, and adjust the camera MFA to eliminate it. Use that to change tuning with the dock. It might be 1.4 times as much using the dock. When there is no movement after tuning the final verification can be done with photos.

fotobyferg

This conversation has gone beyond my pay grade. As mentioned earlier, I have decided to send my gear to Tamron for calibration.

Thanks for all the suggestions though, as I have enjoyed reading everyone’s take on the subject.

What have I learned....I have learned that I don’t enjoy frittering around with technicalities. Give me a good horse and an open trail instead:

SuperflyTNT Loc: Manassas VA

You missed my point. You can use Nikon’s auto fine tuning at each of the focal lengths and distances to get the readings and enter those numbers in the Tap-In.

TonyBrown

I bought a Tamron 100-400 for my partner and had it calibrated by a specialist company. I may be wrong, but I understand that if you get the “tap in” consul process wrong then it can mess up the lens. The lens is now tack sharp on a D7200.

Metis407 Loc: Canada

That's what I am going to do!!

mwsilvers Loc: Central New Jersey

That assumes that the Nikon settings correspond in some way to those entered into the Tap in. And further, Tap-in adjustments to one setting can impact adjacent settings so it is still a long process of fine tuning.

TonyBrown

I paid to have it done. More expensive than buying a tap in consul, but the results at all focal lengths are great.

mwsilvers Loc: Central New Jersey

The Tap-in adjustments are not permanent. You can change them at any time in the future or go back to the factory defaults. Changing settings takes a matter of seconds. Its the testing required to get the best settings that is so arduous. If you put in the wrong settings you can "mess up the lens", but its not permanent. However, having a lens adjusted by a specialist company is generally permanent and its is difficult to go back to the factory defaults.

mwsilvers Loc: Central New Jersey

Was the lens calibrated to your camera body? If so, have you tried that lens on a different body?

TonyBrown

The lens is only calibrated to the one camera. It would need to be recalibrated for use on another camera.

Metis407 Loc: Canada

Calibration by Tamron is free!!

Doc Barry Loc: Huntsville, Alabama USA

If you do enter the Nikon numbers directly, your results will not be what you expect in all likelihood. The Nikon AF numbers and the TapIN AF numbers are not the same. The folks at Reikan have seen a number of calibrations and observed that the Nikon values to TapIN values are related by a factor from about 1.2 to 1.5. Canon I was told is around the 2 range. For my D810 and 150-600mm G2, the factor was about 1.3. How do you know the correct factor? Pick a range and focal length combination and try a few values for the scale factor. I used FoCal to verify the camera optimum AF adj value was zero for the selected scale factor. Then I loaded the scaled AF adj values into the lens using the TapIN.

Perhaps you wonder why Tamron/Sigma need their lenses calibrated at so many points. This is because the range/zoom focus equation is proprietary for Nikon and Canon. Tamron is creating their own equation using the range-focal length AF adj data to determine the coefficients for the Tamron equation. This equation approximates the Nikon/Canon equation performance.

fotobyferg

Was this done specifically on the 18-400 lens? And, if so, you noticed a clear difference in your before and after shots?