Why Image Quality Is No Longer the Most Important Aspect of a Lens

Why Image Quality Is No Longer the Most Important Aspect of a Lens

In any given lens review, the most valued and sought-after tests performed are those pertaining to image quality. I believe we have already begun to shift away from this, and here's why.

If the camera body is the brain, then the lens in the eyes. Without a lens, the brain can't see anything, but how good those eyes are has been of paramount importance for the entire history of photography. People would press their face against prints in decades passed and magnify the pixels in recent times, all trying to decipher lens (and camera) performance. Us photographers wanted to know how every lens stood up to being wide-open, at the optimum aperture, and in high-contrast scenes. We would scrutinize and compare similar lenses to a peculiarity with the express intention of bleeding every iota of image quality out of our hard-earned cash. But, I believe I've noticed a shift, particularly in the last 10 years or so. That is a move away from absolute image quality, to other marketable areas. Before I discuss what I think the primary focus now is (or at least will become), I want to justify my position on why there has been a move away from image quality as the number one aspect of any lens.

Diminishing Returns

It's first important to note that image quality is still important to a lens; more than that, it's vital. I'm by no means claiming that image quality is no longer important, but rather that it is no longer the most important aspect. The reason for this is simply diminishing returns. Diminishing returns is an economical principle that is often borrowed elsewhere as it is so often applicable. Put simply, it is when the yield of any given action reduces over time and with increased production. It is essentially the opposite of something scaling infinitely. With regards to photography, you might look at memory card size.

In 1994, SanDisk (known as SunDisk then) launched their first CompactFlash cards, which were between 2 MB and 15 MB in size. It seems absurd now, but a storage device that didn't require a battery was no small feat back then. By 1996, these cards were being used in digital cameras. In 2004, SanDisk launched the largest capacity CompactFlash card on the market at 4 GB. The small numbers here can fool you into not realizing just how much space was gained in 10 years. A gigabyte has 1,024 megabytes in it, which means in 10 years, the CompactFlash memory cards had increased in storage space by over 270 times. Now, we have CompactFlash cards with a capacity of 512 GB, which is another mighty achievement, but notice the scaling is not exponential here — it's diminishing. In the first 10 years of CF cards, the capacity increased to be 270 times that of the first card. From 2004 to 2021 — 17 years — it has increased by less than half of that, at only 128 times 2004's 4GB cards. From 2004 to 2021, storage space increased 7.5 times. Nearly twice the time and less than half the gains.

Now, memory cards can be a little misleading as the technology changes drastically — CF cards play second fiddle today for the most part — but the optical performance of a lens has been relatively stable for nearly a century. However, we have certainly reached a stage where it has either begun to stagnate or has nearly fully stagnated, and I'm inclined to believe we're closer to the latter. I'm not going down the "everything that can be invented has been invented" line of thinking here. (An aside, that quote is attributed to Charles Holland Duell, and it is wholly inaccurate, as he actually said: "In my opinion, all previous advances in the various lines of invention will appear totally insignificant when compared with those which the present century will witness.") While there can and will still be gains in image quality, they will be minimal.

Gains Past, Present, and Future

In early 2014, I bought a Canon 75-300mm f/4-5.6 — the earliest version for EF mounts — and I got a fairly cheap second-hand copy. I can't swear that the lens I owned was typical for that lens — there are "bad copies" — but I used it a lot. When shooting wide open, which with a zoom lens that has that high a maximum aperture was necessary, it was softer than blowdried alpaca. Even back then, I was disappointed with what it could do when paired with a Canon 5D Mark II. Fast-forward to the present day and even the cheapest zoom lenses are significantly sharper at their worst. The higher-end market for lenses saw far less in gains, it's true, with many top Zeiss lenses even 20 years ago performing well by today's standards. But now, even the lower end of the lens market has nearly caught up on image quality. And it is at this point where the key selling point of a lens has to shift.

There are of course other important metrics that dictate the popularity and effectiveness of a lens — for example, speed. A wide maximum aperture is as desirable today as it always has been, but even that has experienced its own diminishing returns. Few lenses are slower than f/2.8 these days unless they're specialty or medium format. Moreover, much-coveted sub-f/1.0 lenses are far more prevalent and no longer cost a house deposit to attain.

So, when the lenses are fast and sharp with few unwanted artefacts, what else do we want from a lens? What can manufacturers aim for in their design and market? My guess is "character."

The Rise of Character

There have been lenses over the decades that have become cult classics. Yes, it's often in some way tied into the image quality they help produce, but that alone does not raise them into the rarefied atmosphere of revered lenses. Usually, there is some undefined quality that people call the "X factor" or in my case, "character," a visual hallmark of the lens. One of the most modern examples of this is a Fujifilm prime from 2012.

Fujifilm's humble but "magic" XF 35mm f/1.4 R.

The Fujifilm XF 35mm f/1.4 R is widely regarded as one of the best modern lenses made. It is fantastically sharp even wide open, suffers very few common flaws, and manages to remain humble in both form and price. However, there's a word that is often used when describing it: "magic." I managed to trace this back to Fujifilm themselves, when Billy Luong, Senior Technical Brand Manager at Fujifilm Canada went on the FujiLove podcast and discussed the lens. In fact, it wasn't him alone that said it, but other Fujifilm employees responsible for this lens. There was the goal of creating a unique, "magic" look, and this was done, in part, by deliberately creating a lens that was not optically perfect. Of course, it performs well with regards to image quality, which makes it a good lens, but its character, its "magic" is what sends it into a different league.

Whether you consider them overpriced or not, Leica has more or less built an empire off of the pursuit of magic. The Leica look is loved by many, but not because it is the sharpest, or has the least distortion, or the least chromatic aberration. In my own work, I have been gravitating towards lenses with character more often than not when it comes to my portraiture. Sharpness, in particular, is only desirable to a point; once it's at a serviceable level, I don't really care if it increases much further. I want some other quality — something special — to draw my eye. Having the sharpest lens on earth doesn't give you a fluttering feeling of excitement when you look at the back of your camera after a shot, but "magic" might.

The Zenit 85mm f/1.5 manual lens might have been difficult to use, but it had magic in abundance and wide open, and I was plenty satisfied with the sharpness.

In Summary

The diminishing returns of optical quality from lenses mean that the lowest, cheapest lenses on the charts have risen up the ranks enough to close the gap on the higher-end lenses. With image quality from a $5,000 lens varying less and less from the image quality of a $500 lens, the most important aspect of a lens will (and I argue has already begun to) shift. If the only way you can tell an expensive lens from a budget lens, with regards to the images they help take, is by zooming in 500%, few will care. Whereas, if one lens has this difficult-to-define character — that magic — that evokes a response in the photographer and viewers, it will fly off the shelves. Sharpness is, to a degree, expected in modern lenses, so with only marginal gains to be had from great effort, the focus from lens manufacturers will shift to a different metric, and I believe that to be character.

Do you agree that modern lens' image quality is now high enough even at their worst that they are no longer the most important selling point? Do you think I am off base and that image quality will always be the most important aspect of a lens? Share your thoughts in the comment section below.

Robert K Baggs's picture

Robert K Baggs is a professional portrait and commercial photographer, educator, and consultant from England. Robert has a First-Class degree in Philosophy and a Master's by Research. In 2015 Robert's work on plagiarism in photography was published as part of several universities' photography degree syllabuses.

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To me only Image Quality counts. I want the sharpest I can get for the price...

In 2021, the sharpest for the price is the very cheapest native lens. You can pay triple for an f2.8 over an F4-5.6 and only get 5% more sharpness

he likely means sharpest he can get at a given price point, not sharpness per dollar. ie if my budget is $1500, i want the sharpest lens i can get for that amount.

There are so many ways to degrade the sharpness of a lens – movement, filters, aperture. We even use filters to degrade sharpness. For me, character counts. Today we can buy a lens with very good sharpness and character at a reasonable cost. But character can't be easily measured. Contrast and color rendition, along with other attributes, characterize a lens, but they're not easily measured. The character of a lens is measured by the photographer's heart and gut.

For me, this applies to pretty much all gear these days. I think for the most part, the days of buying a new camera/lens/light etc. and having it completey change your photography are over. Pretty much anything is going to take and make great pictures nowadays.

In a world today where a Z 24-200 zoom is as sharp as 24 1.8, 50 1.8, 85 1.8 primes, lens selection decision is mainly down to the size, range, max aperture, price and optical character of the lens. Recently sold my humble Nikon 18-35 G for a newer Tamron 17-35 which is sharper and more contrasty. It turned out to be a bad decisions. I much prefer the old Nikon which has a lower contrast to preserve the highlights in the sky.

Great article! Thanks for taking the time to post it. I think that this will resonate with certain photographers that are probably more focused on getting it right in camera, and I'm definitely one of them. For me, I mostly converted my kit over to Zeiss and Voigtlander lenses because of them having the right level of sharpness combined with character. Zeiss has the 3D Pop (definitely "magic") along with colors that stand out in a very nice manner. Voigtlander has a certain way of producing blacks and tonalities that has a real quality (I would call it professional) look to it. I think it would be a nice extension to this article to interview photographers that are into character lenses and find out the "why" of their lens choices. It's definitely a personal decision and something that can really help tell an interesting story behind their work.

I agree. When shopping for a 135mm portrait I went to B&H and put the Nikkor 135 DC, Sigma 135 and Zeiss 135 and took a quick shot of my BF. I had non photographer friends view each image and all agreed that the Zeiss had more pop and was the most aesthetically pleasing. I know the Sigma is just as sharp in lab tests and has autofocus but the manual Zeiss draws a more beautiful image. Worth the extra money and manual focus.

Another classic showing lots of character is the old Minolta 100mm f2.8 macro...I just purchased a used a77 so I could use it again...Here is a pic with this outfit...

At 20x30 inches I find it difficult to see the difference between my iPhone and my beloved Bronica. And my Pentax's.
My Leicas - 1938 111a and 111b - with Summitar F2 -do not produce the sharpest images, but they do produce the best pix of people.! My digital Leica produces lovely print quality in monochrome.

In the end, good photos depend not on what you hold in your hand, but what is between your ears.

I find that statement interesting concerning the iphone. Ive tried using it but only ever got even half-decent IQ when shooting raw dng via Lightroom. I do - to this day - hate apples image compression algorithms to the core. It creates mushy blobs where there was grass and trees. But like i said, with the lightroom dng workaround it gets a lot better..albeit with very limited dynamic range...

Regarding drawing, I used to hear that it was the Indian, not the arrow. I like to think it applies to photography as well.

Character is great in practice. In reality, it's often just a lenses inability to capture what's actually in the scene.

Not true, the better lens designers do pay attention to distortion, sharpness and other optical issues but also design lenses to render out of focus areas with different aesthetic qualities. for better manufacturers it is intentional and not an accident

The article begs the question. If image quality isn't the most important aspect of a lens, then what is? 'Magic' is a vague answer. Likewise, 'character' is indefinable and cannot be measured. The term image quality encompasses anything and everything the affects the way a lens renders an image. Other than image quality, the other characteristics of lens that matter are things like build quality, weather proofing, size, weight, cost, focal length, max aperture, stabilization, ergonomics, and anything else that does not inherently affect the of rendition of images produced by the lens. The article isn't claiming that any of those things have replaced image quality as most important. Overall image quality is every bit as important as it ever was, even though certain measurable technical elements, such as sharpness, may no longer be significant differentiators of lenses.

Color Rendition and type of bokeh (in particular how bright oof Light-Sources are rendered relative to the focal plane. Also how smooth the bokeh fallof is) are most important to me. To my eye Lenses define Colour balance way more than they should and quite often change the skintone rendering more then the camera body even (always makes me mad to see „Canon vs. Sony Skintones comparisons“ where canon uses l-mount glass and the sony the yellow casting sigma for example...)
The best lens ive used to date must be the sony 35mm 1.4 gm. It resolves such detail and has supernice bokeh and very little abberation, also shows some bright oof highlights. The Zeiss Batis 85is a close second with some of the best Bokeh ive ever witnessed BUUT with a weird shift in yellow/orange tones that can make reddish hairtones look really bad...
Would love to hear other peoples suggestions...
(By the way: i used fujis 23 1.4 and 56 1.2 for a while and was amazed by the 56, but the 35 felt more muddy then „good character“...maybe my copy was bad, but rly didnt like it)

Please add side by side photos of same scene using character lenses and those clinically sharp modern lenses. I am a hobbyist who uses old lenses for the novelty of gaining 95% of the utility of the modern lens at about 5% of the modern lens price, and the pleasure of metal and manual controls. I'll be glad to appreciate character, too.

I think image quality in a lens is just as important as it ever was. Just because people don't talk about something as much anymore doesn't mean it isn't as important as it used to be. We don't talk about it as much because it is taken for granted in new lenses. I mean, food is just as important to people in wealthy first world countries as it is in starving countries, but we don't talk about it as much or think about it as much because it is a certainty; a given. So it is with lenses and image quality (sharpness/resolving ability).

'Image Quality' covers a very large amount of territory. Sharpness, color rendition, flare control, CA control, vignette control, barrel distortion, background blur rendition, and so on. 'Character' is a kind of nebulous description of a lens and is quite subjective. I cite the Canon 85 f1.2 L. Certainly on the list of 'character' lenses. But, it's not that sharp wide open and it focuses relatively slowly. But it has character.

So....is 'character' a way to excuse less than great performance? Hmmmmmm......

I don't have a ton of differing experiences but I went from Micro 4/3rds to Sony FF. No contest. I started with their kit 28-70 lens and trying a number of Rokinon lenses but the Sony 24-105 f4 is amazing. (I'm on a budget so that's my limit.) Not that much sharper on smaller sizes but the look is really nice. I love it. Just wish it wasn't so heavy.

I don't think it's importance. I think it's availability. With advances in lens tech, sharp lenses are easier to find and at lower and lower prices. However, since perfection is now easier to attain, the flaws and quirks that gave character to vintage lenses are disappearing. So, it's not that sharpness is not important, it's that character is getting harder and harder to find.

It's clearly seen that author is not really long standing professional. All that characteristics what you call "magic" and "character" are both described with technical terms long ago and are called - plasticity and rendering. Plasticity in simple words is how smooth is transition area and rendering is how good is image quality in transition area. Since transition area in most cases consist most of the image - what you see in most cases when you looking to most photos is transition area. So transition area defines the perception of the image the most, and whilst most of vendors are pursuing such things as creamy bokeh and sharpness - there are only few ones, who really care about transition area's rendering and plasticity. Most of the premium lenses are very good in transition area, while budget lenses (e.g. Sigma) are good in terms of sharpness and bokeh and transition area is not so good. So good plasticity and rendering of transition area defines "Character" of the lens. That's it.

Nice Article

This is spot on, I think! I am mostly a video shooter and I no longer even hypothetically entertain springing for a cinema lens with the IQ, features, and ease of use available the new lower-cost lenses, including even many of the kit lenses.

In my personal opinion, I say that the quality of a lens will always be the quality, otherwise there would be no lenses from Hasselblad, Phaseone, Leica, Zeiss, Sinaron Schenider, to name a few when it comes to photography, there are the finest for video and film such as panaflex and arriflex