Blurry Corners in a Photo? Don’t Blame Your Lens

Probably the most common image quality issues in photography is to get sharp corners. Landscape photographers (among others) often pay big bucks for lenses along with high resolving power on the edges of the frame. But a new lens may not solve your problem – because fuzzy corners usually aren’t due to the lens.

Personally i think obligated to start this article by saying that corner sharpness is certainly overrated. Many, perhaps even most , photographers don’t need to worry about it very often at all. For instance, I can’t think of a single time that I’ve needed pin-sharp sides for any of my macro photos. I think that most portrait and wildlife photographers will be in a similar boat.  

Still, in some genres of photography, sharp corners are essential. Almost every landscape, architectural, and Milky Way photographer I realize is someone who wants crisp details throughout the frame.

It’s a fact that most lenses are blurrier in the corners. Here’s a plan from a common lens, the Nikon 24-70mm f/4 T at its sharpest central length of 35mm:

Nikon Z 24-70mm f/4 S MTF Performance 35mm

Clearly, the corner sharpness numbers aren’t as high as these in the midframe or middle. This is the case with almost every lens on the market today. So , it is tempting to blame your zoom lens if you’ve taken a photo along with blurry corners.   That’s especially true if everywhere else in the photo looks great, and the corners are the just blurry regions. Surely the glass is to blame at that point… Or could it be?

Looking closer at the diagram above, you’ll notice that the corner sharpness in fact reaches quite a high level. In fact , at its sharpest aperture of f/5. 6, the corners on this lens are simply as sharp as the center is at f/11! Have you ever made a large print from a picture taken at f/11? I actually certainly have, and even at pretty huge print sizes, photos at f/11 can look very sharp. Plus, this is just a kit move (albeit a good one). Nearly every modern prime has much more corner sharpness than this particular.

In other words, along with nearly any lens today, you should be getting at least enough detail in the corners of the images to make sharp, wall-sized prints all the way out to the extremes of your frame.   So , what if you aren’t? The truth is that there are many reasons why the corners of an image could be blurrier than the center, aside from a low-quality lens. In this article,   I’ll discuss 4 of the most important factors and how to make sure they don’t lead to fuzzy corners in your images.

Table of Contents

Insufficient Depth of Field

In most landscapes, the nearest thing in your photo is going to be along the lowest edge of the image. In fact , it is often in one of the two foreground sides.

You might think that this bottom center of the picture is usually where the closest object would be. But from the perspective of depth of industry, that isn’t true. In real-world landscapes, there are generally slight slopes and protrusions to the foreground in front of you. The end result is that the single closest item (to the plane of your camera sensor, that is) will certainly fall in the corner much more frequently.

The photos below are examples of typical landscapes at both wide-angle plus telephoto perspectives. In both examples, the nearest object is in a corner rather than the bottom middle. In this image, it’s the particular patch of sand at the lower left:

Wide angle sand dunes landscae with closest object at bottom left corner
Canon EOS 80D + EF-S 18-55mm f/4-5. six IS STM @ 21mm, ISO 100, 1/250, f/9. 0

And in this shot, it’s the grove of trees and shrubs at the lower right:

Telephoto landscape Tuscany with closest element in the bottom right corner
NIKON D800E + 70-200mm f/4 @ 130mm, ISO 100, 1/10, f/11. 0

If you think that these examples are atypical, I encourage you to look through your own landscape pictures with a close eye. I believe you’ll find that the closest objects appear in the edges more often than anywhere else.

Personally, after scanning my landscape photography portfolio of 45 images, I confirmed that this held genuine. In six of the photos, the closest object was at the bottom center. In the meantime, in a whopping seventeen pictures, it was at one of the bottom level corners. (In eleven photos, everything was at infinity, and in the remaining eleven, the entire bottom edge of the framework was equally far from the lens. )

This all leads to myself saying: You might not have a corner sharpness problem, but instead a corner level of field problem ! If your corners are nearer than anything else in the photograph, they’ll be disproportionately affected by a shallow depth of field – no matter how good the lens is.

Depth of industry is already one of the biggest issues lots of landscape photographers face within getting sharp shots. It would appear that many photographers take pictures at wider apertures such as f/4 or f/5. 6 because those are the sharpest test-chart apertures, even when the real world scene in front of them demands f/11 or f/16 pertaining to proper depth of field. Yes, there’s more diffraction at those apertures, but there’s much less blur from out-of-focus areas. It’s really worth the tradeoff, especially if you want your corners to look sharpened.

Wide Angle landscape photo with nearby foreground in the corner at f16
NIKON D800E + 14-24mm f/2. 6 @ 20mm, ISO one hundred, 0. 8 seconds, f/16. 0

That’s all fine and good when you have a close downroad, you might say. But what if every thing is in the distance, and your edges are still blurry? It could be a poor lens, but it  still   could be that you lack depth of field. This is particularly genuine if you’re shooting with a telephoto lens.

Telephotos have less depth of field than wide sides, and “infinity focus” having a telephoto can be quite distant. You may have some objects in the bottom corners of your frame that are further out-of-focus than you thought.

Within the photo below, I had in order to shoot at f/16 since the fence at the bottom – distant though it was – still was close enough to become out of focus at f/5. 6 or f/8. Even at f/16, it’s barely within my depth of field, and the corners are still slightly weaker in clarity than the rest of the frame.

Rainbow at sunrise
NIKON D800E + 70-200mm f/4 @ 130mm, ISO 100, 1/2, f/16. 0

It’s also possible that your lens could have significant  field curvature   – enough to harm corner sharpness, even when the lens is technically razor-sharp enough to resolve those details. Field curvature is also the depth of field issue, although this one is the particular fault of your lens. Nevertheless,   stopping down adequately (or focus stacking) is sufficient to fix it.

In any case, there’s an easy way to determine if your corner sharpness woes are the result of depth associated with field or not. Simply re-focus your lens directly on the image. If the corner abruptly looks a lot sharper, congrats! You don’t need to buy a new lens after all. You just need to use a technique that guarantees your depth of field intersects with the nearby edges of your frame.

Incorrect Focusing Distance

Together similar lines as an insufficient depth of field, you may even be placing that depth of field (i. electronic., focusing) in the wrong spot.   Take the example diagram below:

Focusing Distances Illustration Flower Mountani Landscape Photography

Which flower would you focus on if you want to maximize depth of field from the front towards the back of the frame? (In other words, the focusing distance that equalizes the sharpness of the closest floral and the distant mountain. )

If you aren’t already familiar with the topic I’m about to mention, it may seem logical to focus on one of the middle blossoms, or maybe one of the slightly nearer flowers, like the one that is 4 feet away approximately. You’re probably also thinking that it’s a bit of a guess plus depends upon how the scene discusses the time.

Actually there’s no guesswork needed; the diagram above has all the information you need in order to determine the mathematically best place to focus. To be specific, the particular focusing distance that maximizes your sharpness from tailgate to cab is the flower at two feet away, because it’s twice as far away as the closest object in your photo. This particular “twice as far” point is very powerful, since it equalizes foreground and background sharpness no matter what focal length you utilize. I’ve already explained it in detail in my articles upon hyperfocal distance   and the double the length focusing method , so I won’t go into it once again here.

Be sufficient to say, many landscape professional photographers focus too far away usually if they’re after the optimum depth of field – and, therefore , optimal corner sharpness in the foreground.   Even if you’ve chosen an aperture that gives you lots of depth of field, a bad choice in your focusing distance can place that DoF incorrectly and come back to queue you.

Color version of sand dune shadow photo
Sony A1 + FE 70-200mm F4 G OSS @ 70mm, ISO 100, 1/60, f/16. 0

And yes, lens sharpness can still play a role in making things worse. Even though nearly every modern lens is razor-sharp enough throughout the frame, the corners are   the blurriest parts of a lens. If you combine that blur, slight or not, with the additional softness from out-of-focus areas, it’s no wonder that so many photographers are getting blurry corners!

As before, focus stacking is still a viable option to fix the focusing range problem, but I find that it’s only needed in the most extreme of instances. Usually, the proper focusing range combined with a narrower aperture will clear up the edges all on its own, while still leaving the rest of the frame extremely sharp.

Uneven Effects of Camera Shake

An additional cause of disproportionately blurry corners is camera shake. Should you be shooting handheld, this is especially true, yet tripod-based photography can come across shake issues as well. In windy conditions (or something similar like putting your own tripod legs in a stream), you may think that your setup is stable, and even see evidence of that with sharp leads to the center of your image. But camera shake almost always impacts some parts of a photo a lot more than others.

To become specific, if there is any rotational shake happening in your digital camera system, the center of the image may look sharp even when the edges look like mush. Virtually all the blurry corners I realize in handheld photos – and some in tripod-based pictures – have camera shake as the root cause.

Try it: Set your shutter speed close to the limit associated with what you can capture dramatically handheld, like 1/40 2nd for a 50mm lens, or even 1/3 second if you have good image stabilization. Then capture a handheld picture of the brick wall focused within the center. (I know that packet wall photography is taboo in some corners of the photography world, so if anyone yells at you, say that Spencer told you to do it. ) I bet you’ll get very good sharpness in the center whenever you zoom in, while the sides will look much worse. Today repeat the same test at a higher ISO and a shutter speed like 1/250 2nd. The center might look about the same, but the corners will look crisper!

I did that here, photographing some wonderful aspen trees instead of a packet wall:

Handheld Photo of Red Aspen Trees Taken at 0.3 seconds
NIKON Z 7 + NIKKOR Z 24-70mm f/4 Ersus @ 45mm, ISO 64, 1/3, f/11. 0

The photograph above was shot portable as a test of the Nikon Z7’s in-body image stablizing system. I’d say this worked pretty well, with the center of the image looking extremely sharp in a 100% harvest:

Central crop of aspen photo that looks sharp
Center, completely crop

What about the corner? Much worse:

Corner Crop that shows blur from camera shake
Corner, totally crop

The blur in the image above isn’t due to a poor lens, but almost entirely due to handheld camera wring! Actually, this is why I find most claims from digital camera companies about image stablizing to be overly optimistic just for real-world shooting. Yes, I have taken photos at 70mm handheld at 1 2nd with modern IBIS. And the ones photos are sharp, as well – in the center. But the edges and corners rarely hold up well. For photographing something like portraits or blossoms, the 6, 7, or even 8-stop image stabilization states from today’s companies might be accurate, but they fall short when you need sharp corners.

Uneven Motion Blur

Your fourth and final reason for fuzzy corners that I’ll protect in this article is motion obnubilate in the scene itself. Even if everything in the scene is certainly moving at a similar rate (like grass blowing in the wind or ocean dunes rolling onto shore), the particular corners of an image generally bear the brunt of the blur in an image.

Why is that? For the simple reason that the items in your corners are so near to your camera. They’re magnified – which means their movement blur is magnified, as well.

The simplest sort of that is an ocean influx. Take a look at the photo beneath:

Motion blur in the foreground at Jokulsarlon beach with an iceberg on shore
NIKON D800E + 24mm f/1. 4 @ 24mm, ISO hundred, 1/2, f/16. 0

In this picture, I obviously don’t care about corner sharpness, and even prefer that the water in the foreground has some nice motion blur. But you’ll notice that the particular waves in the distance, specifically close to the horizon, don’t appearance very blurry. They were, naturally , moving at the same speed as the wave that just crashed ashore. But because the foreground wave is so much closer, its motion blur is more magnified!

This same thing will happen when there are rustling leaves or cutting blades of grass in your frame. They might be perfectly sharp within distant regions of the photo, yet full of motion blur in the nearby corners. Once more, the lens isn’t to blame, and better technique (like a faster shutter rate or better timing to get a lull in the breeze) is needed.

Lastly, something similar can happen in astrophotography depending on the direction you point your lens. In the photo below, it’s pretty obvious that the stars at the corner are blurrier than those within the center, and not because there are a fault with the zoom lens:

Blurry corners in astrophotography due to star movement
NIKON Z . 6 + 20mm f/1. 8 @ 20mm, INTERNATIONALE ORGANISATION FÜR STANDARDISIERUNG 800, 120 seconds, f/2. 2

I took the picture above with a 120 2nd exposure to exaggerate the effect, however it still appears at a lot more typical Milky Way shutter speeds like 20-30 seconds. This star movement won’t always affect the corners more than the center, but in many situations, it will.

Conclusion

If you’re the type of photographer which hates blurry corners, I hope this article gave you ideas of how to avoid them. I also hope it helped decrease your gear acquisition syndrome (GAS) a bit.

Indeed, some lenses have sharper corners than others. And if you’re shooting with decades-old glass, it might be time for an upgrade. But in the vast majority of situations, unsharp corners have a cause other than the lens. It could be your depth of field, focusing distance, camera shake, or motion blur. When you can minimize all these sources of obnubilate, you’ll find that you can take pin-sharp photos throughout the frame despite an inexpensive lens.

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