Why you should AF Fine Tune Nikkor Lenses – Reikan FoCal

Since the introduction of the Nikon D3 way back in 2007, middle to high-end Nikon camera owners have been able to adjust the focus system of their camera to work better with each lens.Why you should calibrate Nikon Nikkor lenses with Reikan FoCal

Reikan FoCal takes the guesswork out of this adjustment by automating the process and using advanced computer analysis to determine the best adjustment for your camera and lens. Over the past 5 years, FoCal users have been uploading their results to our database, and we process this information and feed it back to let them compare how their camera and lens compares with everyone else.

The last post looked at the detail about the real world need for AF Microadjustment on Canon cameras with Canon EF lenses, so I wanted to now take the same look at Nikon cameras with Nikkor lenses to see if things look about the same.

Another Spoiler Alert!

Not surprisingly, it turns out the results for Nikon lenses follow pretty much the same pattern as Canon lenses, albeit with a little bit of a stronger conclusion:

For most Nikkor lenses, there’s a 1 in 2 chance you’ll get a significant improvement in image quality by adjusting your autofocus with Reikan FoCal.

But don’t just take our word for it.  I’ve shown below the information for each of the lenses we have data for.

Nikkor Lenses

The Nikon F Mount was introduced in 1959, and since then some 400 Nikkor lenses have been produced.  Although older lenses are still compatible with new cameras, there are many more users of more modern Nikkor lenses on FoCal-supported cameras, so our database contains a little over 60 different Nikkor lenses with high quality data associated.

As with the similar Canon post, I’m going to use the results to show how likely it is that any particular lens will benefit from calibration. I want to try and answer the question:

“When I take that shiny new lens out of the box, what are the chances that I’m going to get the best from it without any adjustment?”

How likely is is that a lens needs no adjustment at all?

We’ve taken all the data and worked out the percentage of each lens type that required no calibration at all (i.e. the AF Fine Tune result from FoCal was 0). Here’s that data shown for all the Nikkor lenses (ordered from most-likely to least-likely to be just perfect out the box):

Reikan FoCal - Nikon Nikkor Lenses requiring very little calibration

(Note: click on the chart to see a large view)

Let’s start at the very left of the chart. The Nikkor 500mm f/4 lens has a value of around 13%… so what does that mean? It means that – on average – if you had 7 of these lenses on the bench in front of you, 6 out of 7 would produce sharper photos if you ran them through FoCal. Only 1 of the 7 (13%) would not need any calibration. And that’s for the best on the list!

Move to the fifth lens on the chart (to the 10-24mm), and you’re down to less than 10%, i.e. more than 9 out of 10 lenses would benefit from calibration!

And at the far right, the last lens types (the 400mm f/2.8) could do with calibration for every single copy of this lens!

Which lenses need just a little adjustment?

To be honest, we’ve gone for a pretty stringent requirement above of needing a calibration result of zero.  In reality, you’ll usually not notice much of a difference with an adjustment of 2 AF Fine Tune points, so let’s have a look at what happens if you include all the results that needed just a small amount of calibration (-2 to +2 AF Fine Tune result):

Reikan FoCal - Nikon Nikkor Lenses requiring a small amount of calibration

Things are looking a bit better here…

Again, starting at the far left, this time it’s the Nikkor 18-35mm f/3.5-4.5 that’s best, and our number has jumped to around 50%. So now 1 in 2 of those lenses won’t need an AF Fine Tune of more than +/-2 points.  But conversely, we’re saying that 3 or more AF Fine Tune points starts to mean a significant image quality improvement, and that means that the other half of all Nikkor 18-35mm lenses (the best in this list) would benefit from calibration.

Let’s think about that…  over half of all tested Nikkor lenses would see a significant benefit from calibration.

For the half of the lenses on the right side of the chart, you’ve got more than a 80% chance that you’ll see a significant improvement using FoCal.

What does this adjustment look like?

I keep mentioning tiny, small and large calibration differences, but what do these actually look like?  The images below show the difference between a well calibrated Nikkor lens, and an offset of 2 AF Fine Tune points (barely any noticeable difference), a 10 point error (significantly blurred), and a 20 point error (hugely blurred):

Reikan FoCal - example of AF Fine Tune error images for Nikkor lenses

The yellow chart above (Percentage requiring very little calibration) shows the percentage of lenses that fall somewhere between Calibrated and 2 point error.  The remaining lenses – that’s more than 1 in 2 lenses for 80% of the different lens types – are somewhere between 2 point error and 20 point error!

Another thing worth noting is that autofocus isn’t perfect and can focus on slightly different positions with each shot.  By calibrating with FoCal, you not only improve the absolute image quality you can achieve, but you also improve the likelihood of achieving a better quality image.

The Scary End!

Finally, let’s take a look at the scary end of the figures – the lenses which needed a huge calibration (more than 10 AF Fine Tune units):

Reikan FoCal - Nikon Nikkor Lenses requiring a huge amount of calibration

This time, the left side of the chart is a bad place to be. If you had 10 copies of the Nikkor 80-200mm lens on your desk, typically 6 out of 10 of them would get a massive improvement (more than 10 AF Fine Tune points) after calibration with FoCal!

The number does drop, but for majority of lenses you’ve still got a greater than 1 in 5 chance that you’ll need a really big adjustment (more than 10 AF Fine Tune units) to get the best from the lens.  And to put that in context, all of those lenses will be producing results between the 10 point error and 20 point error images above!


There’s a pretty simple conclusion here: you really should run every lens you have through FoCal’s Fully Automatic Calibration!  For Nikon, this applies even more so than our findings with Canon EF lenses.

For most Nikkor lenses there’s a high chance you’ll get a noticeable improvement (3 or more AF Fine Tune points) in image quality after calibration, and for around 1 in 5 you’ll get a massive improvement (more than 10 AF Fine Tune points).

FoCal takes all the guesswork out of adjusting your lenses, so for the sake of a few minutes with each lens it really is worth it to get the best from your kit.

Take a more detailed look at FoCal on the website.

22 comments on “Why you should AF Fine Tune Nikkor Lenses – Reikan FoCal

    • Hi Steve,

      Thank you for your interest in Reikan FoCal.

      FoCal works really well with longer lenses, if you shoot wide open or close to wide open you will more often than not see a large improvement in focusing especially with longer lenses (due to shallow depth of field). Note with lenses over 400mm length FoCal Pro is required, see also Which version of Reikan FoCal should I buy?

      Best Regards,

  • as I have a number of lens if I calibrate each lens and let’s say they have all differ value.
    do I have to run calibrate each time or just remember values and put them in the camera

    • Hi George,

      Thank you for your interest in Reikan FoCal.

      Once a calibration is made for a camera/lens combination the camera stores that calibration result internally. When the lens is re-attached the camera recognises the lens and applies the previously stored calibration setting. There’s some good videos that give lots of background info, see Are there any FoCal calibration videos I can watch?

      Best Regards,

    • Hi Robert,

      Thank you for your interest in FoCal.

      Sorry to say at this time FoCal works only with Canon and Nikon dSLR which support AF Microadjustment / AF Fine Tune. See also FAQ entry Is my camera / lens supported by FoCal? for some background 🙂

      I won’t say the Pentax line of cameras will never be supported but at the moment it’s not on the plan due to restrictions on the way we might be able to interact with the camera.

      Best Regards,

  • Steve Tenney says:

    How about calibration with the Nikon TC-1.4EII teleconverter. I’ve completed the calibration and gotten values like +5, +13, +1 & +4. Consistently getting poor fit result on the Nikkor 300mm f/4D IF-ED lens. The lens by itself shows a -2 with a Good fit result.


    • Hi Steve,

      You should be able to get the lens+TC to give accurate results, worth checking the FAQ What does “Fit Quality” mean within FoCal calibration results?. It may come down to lighting, often more light is better as it provides a faster shutter speed (reducing any shot vibration) but also helps the AF system itself to be more consistent. Do raise a support ticket if we can help further (blog comments aren’t the best place for support!) 🙂

      Best Regards,

    • Hi Rudi,

      At the moment the Nikon D850 is not supported by FoCal, but support is coming soon!

      Nikon has not yet provided an update to their comms library module for the Nikon D850, this is needed by FoCal before we can provide support. The Nikon library is normally made available around a month or so of the camera being released.

      We’ve done all the up-front work possible and once we have the updated software from Nikon it will likely take a couple of weeks for an updated version of FoCal 🙂

      Best Regards,

  • Chris Patterson says:

    Hi Focal. I am a subscriber to your newsletter. Are you guys engaging with Nikon to get the timing on the update to their comms library module for the Nikon D850?

    • Hi Chris,

      Thank you for your interest in FoCal.

      We have been waiting for the update from Nikon for the comms library.

      Earlier this week (late Tuesday) Nikon went ahead and provided the update so work can progress!

      Always tricky to have a exact timescale (development is not always a straight line!) but we’re aiming for 3 weeks or so 🙂

      Best Regards,


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