Have you ever looked through your camera’s viewfinder only to discover a blurry image? If so, your camera diopter is probably set incorrectly. Luckily, it’s easy to fix.
In this article, I explain how you can reset your camera’s diopter so your viewfinder always looks sharp. I’ll also explain how you can use your diopter to shoot without glasses or contacts. (That way, you never have to worry about bad vision ruining a photoshoot!)
Let’s dive right in.
What is a camera diopter?
A diopter controls a lens system in your camera’s viewfinder, and it allows you to match the focus of your viewfinder to your eye.
A poorly focused viewfinder image – one without a proper diopter adjustment – will look like this:
But adjust the diopter, and you’ll see something more akin to this:
Note that diopters are offered by most DSLRs and mirrorless cameras. You can generally find the diopter control on the left or right side of the viewfinder.
Also note that a diopter does not affect the actual sharpness of your photos; it only affects the sharpness of the viewfinder. In other words, a blurry viewfinder doesn’t translate to a blurry image.
Why is a diopter useful?
Camera diopters allow you to see the sharpest-possible image – so you can carefully select points of focus, compose your scenes, and analyze subject detail.
After all, if you’re looking at a blurry scene through your viewfinder, how can you expect to capture a good shot? You won’t be able to get an accurate feel for the scene because you’ll be hampered by the blur!
If you wear glasses, the diopter adjustment can be a huge help. You can use it to correct for your bad vision; that way, you can shoot without glasses. Or, if you sometimes work with glasses and sometimes work without, you can adjust the viewfinder before each photoshoot so you see a clear image.
I’m always shocked by the number of students who tell me they never see anything sharp through their viewfinder. I show them the diopter, and after they’ve made a quick adjustment, they’re often surprised by how sharp the viewfinder appears!
How do you know your diopter needs adjusting?
If you look through your viewfinder and you see an ultra-sharp image, then your diopter is properly set and can be left alone.
However, if you look through your viewfinder and notice blur – even a bit of blur – then you should follow the adjustment steps I share below.
Pro tip: When evaluating the viewfinder, try pointing your camera at a scene with plenty of details, such as a poster or a book. If you struggle to read the words or resolve fine lines, it’s a sign you need a diopter adjustment.
(You can also look at the information and guides present in the viewfinder, such as the exposure bar and shutter speed numbers. These should be tack-sharp; if you can’t see them clearly, your diopter needs resetting.)
How to adjust the camera diopter: step-by-step instructions
Making a diopter adjustment is quick and easy. Just follow these steps:
Step 1: Locate the diopter control
The diopter is generally a small wheel or slider close to your camera’s viewfinder:
Most are labeled with + and – signs.
Step 2: Put your camera on a tripod
Make sure you have a lens attached to your camera – ideally, a sharp lens that can focus relatively close.
Then mount the camera on a sturdy tripod. Place the setup in front of a flat scene with decent detail and good contrast, such as a bookshelf, a clock, or a brick wall.
Step 3: Focus the lens
Using your lens’s autofocus, focus on the scene.
(If you’re using a manual-focus lens, that’s okay, but you’ll need to be extra careful to ensure accurate focusing.)
Take a test shot, then zoom in to view the details on your LCD. Make sure the results are crisp. (If you have a mirrorless camera, you may be able to view the image through the viewfinder, but do not do this! Verify accurate focusing without looking through the EVF.)
Step 4: Adjust the diopter
Look through the viewfinder. Then start to turn the diopter wheel or move the slider.
The image may get sharper or softer. I’d recommend pushing the diopter adjustment until the viewfinder looks extremely blurry; then bring the diopter back until you see a tack-sharp image. (Feel free to push it back and forth until the viewfinder is as sharp as you can get it.)
Note: If the viewfinder display information looks sharp but the image never fully comes into focus, then you have a different problem. You may have misfocused, in which case you should repeat the previous step. Alternatively, you may be using a soft lens or a lens that’s unable to focus at that distance; try switching lenses and/or backing up and see if it solves the problem.
Step 5: Repeat as necessary
If you always photograph with glasses or contacts, wear them when you set the diopter; if you first adjust the diopter and then put on your glasses or contacts, the viewfinder may feel heavily overcorrected.
Of course, if you prefer to photograph without glasses or contacts – even if you wear them in other situations – remove them before adjusting the diopter. The diopter can compensate for poor vision, but only if you set it to your eyes.
Finally, if you sometimes photograph with glasses or contacts and sometimes photograph without them, simply reset the diopter before each new photoshoot. It’ll only take a few moments, and that way, you can be sure that you’re capturing the sharpest-possible photos!
The camera diopter: final words
Camera diopters aren’t complex, and adjusting your diopter is simple. Yet it can make a huge difference to your photography – and your photographic enjoyment – so don’t be afraid to do a reset every now and again!
