One question I got from one of my students inside our student only Facebook group recently was “Do I need to calibrate my camera lens? I keep hearing it talked about but I’ve never done it and I don’t know what to do!”

It’s such a great question, one which every single one of us will ask at some point, which is why I wanted to tackle it here on the podcast today!

I’m going to cover what lens calibration is, why you might occasionally need it and how to know you if you need to do it right now.

Plus I’ll give you a quick and dirty test you can do with your lenses, and a guide on how to actually calibrate should you need to do so.

Before we dive into the need and how, let’s rewind a little bit for any photographers and talk about what lens calibration actually is.

What Is Lens Calibration anyway?

Camera lens calibration is the process of fine-tuning the autofocus system of your camera to ensure accurate and precise focus.

Basically, if your lens needs calibration, it means there’s a slight miscommunication between the auto focus of camera and the lens, and when you calibrate, this simply corrects how ‘off’ the lens is.

Essentially you are matching up the lens to the camera’s autofocus chip so that they are both seeing the same thing.

You do this by getting into your autofocus system on your camera and adjusting it, to ensure that the lens always focuses accurately on your subject.

Why your lens MIGHT need calibrated

To understand why there might be a problem with the auto focus, let’s start by looking at how this happens.

All cameras and lenses are manufactured to be with a certain range of accuracy.

So, for example, your camera may focus to the back ever so slightly, but it’s within an acceptable margin that is virtually unnoticable. It can also be the same with your lens - it could front or back focus ever so slightly, but be within that “tolerance” that it’s not noticeable,.

But when you put these two slightly-off items together, you end up with a bigger problem. If your camera back focuses every so slightly, and then your lens back focuses ever so slightly, when you use them together it’s enough to take the focus out of that acceptable range.

So both on their own may be fine, and the problem only happens when you put them together.

There is also the situation where the lens was shipped out without focus being in that acceptable range.

This is really unusual (but not totally unheard of) with high quality lenses because Canon and Nikon and so on have really good quality control on their lenses, but with cheaper lenses, they don’t have the same stringent quality controls so it can be more likely that these are a bit off.

The other thing to note is that over time, the miscommunication between the lens and the camera’s autofocus chip can shift and cause your focus to be off, so even if your lens was fantastically sharp and accurate when you first got it, this can go over time!

Signs that your lens needs calibration…

If you start to notice that your image looks focused in the viewfinder, but when you view the image later on the computer screen, focus seems to have landed elsewhere, then this could be a sign that your lens needs calibrated.

For example, say you are photographing a person, and you aim your focus point on the eye, but then when you view the image zoomed in, you’ll see that the focus is on shoulder instead of their eye. In other words the focus is always a little bit off, and critically, always in the same direction, in other words focus always lands a little to the front or to the back.

This is more noticeable when shooting wide open, because the depth of field is so narrow.

I should point out that a lot of the time, images are soft due to user error, not because the lens needs calibrated!

There are so many factors that go into getting a tack sharp image (and that can stop us from getting one) it could simply be that you’re not doing it right, rather than the lens being the problem. (Which is why we have a whole module devoted to it in our Auto to Awesome course!)

If this is the case, you’ll see that focus lands elsewhere but it’s different each time, so not always to the back (for example)

So if you are not consistently getting the sharp focus you want, it might be an idea to quickly test your lens, that way you’ll know whether you have a problem with your equipment or if it’s user error.

If you do have a problem, then you can calibrate your lens to fix it, and if you don’t, well, at least it will put your mind at rest that your equipment is fine and you simply need to learn the techniques and strategies for getting sharp focus with different subjects!

In Auto to Awesome, there’s a whole module, and I think 6 lessons, purely on focus, because there is SO much that goes into making sure your photos are tack sharp.

So, the short and curly answer is you only need to calibrate if and when you notice that your focus is consistently off when you use a certain lens, either when you immediately get the lens, or after a couple of months or years of use. So if you always used to get sharp photos, but now you don’t, then that’s a clear sign to test your lens.

(As a side note, you won’t need to calibrate is if you have a mirrorless camera. That’s because mirrorless cameras do not use an autofocus chip - the camera’s sensor takes care of both, so there can’t be that same miscommunication that you get with a DSLR)

How to test whether your lens needs calibrated!

OK, so you’ve noticed that your focus is always a little bit off, but how do you check it?

There is a super simple check that will tell you whether you have problems, and you can do this for free with a set of batteries, or if you have around $10 to spare, you can use cheap and cheerful lens calibration tool like this one that I used.

For the batteries option, you can see exactly how to do it in this blog post I wrote a while back, or you can do it with a lens calibration tool which looks like the image below.

When using the calibration tool, you need to use a tripod, and then place the focus point on the QR code, and you should see focus land on the 0.

If focus lands BEHIND the 0, then your lens is back focusing.

If the focus lands in FRONT of the 0, then your lens in front focusing.

If the focus lands on or very near the 0, congratulations! Your lens is focusing perfectly.

How to calibrate your lens

If your lens DOES need calibrated, then you have two options available to you :

#1 - Send it in to get calibrated to your local camera shop, or send it to the manufacturer such as Canon or Nikon. This should cost somewhere between $50 - $100.

Please note you will also need to send in your camera with your lens, so you’ll be without your camera for a little while!

#2 - If you don’t mind getting into the settings of your camera and mucking about with the auto focus, then the second option is to DIY it with a lens calibration tool.

Let’s take a closer look at how to do that…

Tools needed for lens calibration.

To calibrate your camera lens, the first thing you will need is a calibration tool.

There are numerous options available, all at various price points.

Here’s some suggestions:

DSLRKIT Lens Focus Calibration Tool (this is one I have)

SpyderLensCal

JJC Calibration Tool

DIY Lens Calibration

Calibrating your lens can be done using a process called micro-adjustment, which involves making small adjustments to the focus of your lens to ensure it is properly aligned with your camera body.

Before you do anything else, grab your camera manual or get into the camera settings menu, and look for something called AF Microadjustment or similar.

Here’s what they’re called for different manufacturers:

Canon – AF Microadjustment
Nikon – AF Fine Tune
Sony – AF Micro Adjustment
Olympus – AF Focus Adjust
Pentax – AF Adjustment

You want to check that you have this option because not all camera models allow you to do this.

So find this first, and if you have it, take a note of where it is as this is where you are going to make your adjustments when you get to that part in the process!

You’ll get instructions with your chosen Lens Calibration Tool on how to use each one specifically, so refer to that on how to do it, but essentially you will need to:

Find a room with lots of natural light and put your calibration tool on a flat, steady surface
Pop your camera on a tripod (you need to ensure that you’re not moving the camera when you focus and it stays on the same spot, otherwise it won’t work. You can use a flat steady surface instead)
Ensure that the camera and ruler are level with one another, exactly perpendicular and at the same height.
Set your lens to the widest aperture.
Focus on the area designated on your lens calibration tool and take a photo.
Check where the focus has fallen - was it in front? Or behind? (It’s recommended to do this on a computer rather than on your camera’s screen!)
Use your camera’s AF adjustment setting (the one that you located above!) to fine-tune your focus, before taking another test shot, moving the slider to the + or - side depending on whether the lens was front or back focusing. (You will need to check your manual to how to do this specific to your camera make and model)
Repeat until focus is landing exactly where it should be.

One final thing to note - this only fixes ONE lens by matching it to the camera, so while you are there I would suggest doing it to all your lenses!

Benefits of calibrating your lens.

If your lens was way off, you should notice that you get more accurate focus, and stop getting those slightly out-of-focus photos! Yippee!!

However, if the adjustment was minor, please don’t think this is a magic pill that means all your images will be tack sharp all of the time!

Using the right focusing techniques, modes and strategies will help far more that making small micro adjustments with your lens focus.

In other words, calibrating your lens is just one little element of a whole arsenal of strategies that you need for sharp focus.

If you want to know more, do check out our Auto to Awesome program which covers focus, along with camera settings, exposure, manual mode, composition, light and more!

Thanks for being here, and I’ll see you again next week!

Audrey x