Have you ever had a lens that you love but overtime you find it becomes dull and the focus becomes inaccurate?
Lens calibration might be the ticket to solving your issue!
I assume many of you are like me and feel that accurate, sharp focus is one of the most important things in an image. I’m a pixel peeper and want to see my children or subject incredibly sharp.
This is very important because I’m a very wide shooter and my aperture sits anywhere between f/1.2-f/1.6 daily. If my lens is not calibrated properly it’s very noticeable.
See the image below? As soon as I shot this I realized it was time to calibrate my lens.
If you look closely you’ll actually see the focus fell in front of my daughter. This is called front focusing. If the focus fell behind her, meaning past where she was standing, this is called back focusing.
Whether your lens is front or back focusing is not really the issue. The issue is the focus is not hitting the anticipated target. Yes, there can be user error in situations like this but if you see it happening consistently it’s time to calibrate your lenses.
We’re all busy and the thought of calibrating lenses to me always seemed so time consuming. I would often struggle with finding the time to complete the task. I needed to figure out a quick and easy way for me to calibrate my lenses.
Below I’m going to walk you through an easier way to calibrate your lenses. I’ve found it to be fast and effective.
Not all cameras have “micro calibration” (Canon) or “Fine- Tune” (Nikon) as an option so you need to check your manual first.
To begin, make sure you are in a well lit room. You’ll also need to have a table or long bay window accessible. I would prefer to use a table but my current home doesn’t get the correct amount of light in our kitchen, therefore I use the bay window in my living room.
I place my camera at one end of the window and then use a calibration chart at the other. You don’t need to have this type of chart to complete the process. There are charts, like the one shown, that can be printed from the internet in which you can place a ruler on an angle to help you see where the camera is focusing.
You’re welcome to use any object with contrast such as a doll. I would not use anything that can move such as people or pets as your focus object. The reason for this is that the object needs to stay in the exact same place. If the object moves just slightly it can cause your calibration to not be accurate.
You also need to keep your camera at the same distance from your marker. Placing your camera on a tripod is recommended.
Next, I open my lens up to the widest aperture possible. I then adjust my ISO to be as low as possible, preferably around 100-200. Then I adjust my shutter speed to accommodate the other settings to create accurate exposure.
I make sure my center focus point is lined up exactly where I want focus, which is in the center of the chart. After I click the shutter three times, I look at my LCD screen and zoom in as far as I can to see if the correct focus was achieved. I like to use my LCD screen because I have found it to be as effective as uploading to the computer and reviewing between each adjustment. It save a lot of time and has the same accuracy.
I repeat these steps exactly the same except I change my micro calibration to + or – 5, 10 and 15. You can tell pretty quickly if the camera is front or back focusing. Below you will see the difference with each one.
Here is a comparison on my daughter’s eye. This is set at a 3:1 ratio.
Once you’ve completed this and your focus is on point again, make sure to test it out before heading to a paid session. Many times, you won’t have an issue but it’s always a good habit to check your gear.
Remember that your lens can become soft again as time goes by and you use it. Be sure to check your calibration regularly.