Why the lens does not matter...the impact of Six Sigma on Lens Quality

Photo by Paul Skorupskas on Unsplash

I love gear. I like the feel of it, I like the hunt for it and I like to be able to put my hand into a bag and pull out the perfect tool for the problem I have to solve. I understand that gear does not make the photographer, but I get an enjoyment out of my gear that I do not want to give up for the sake of the "art first" crowd. 

But here is a hard truth to swallow....the lens does not matter. Yes I said it. It does not change a thing. Now let me explain...yes the focal length matters a great deal, the aperture can change the feel of a photograph completely but the lens quality does not matter at all...except in one little instance...let me explain.

Let's talk image quality. Can the lens impact this? Well sure if you are looking at the lenses made pre-1990. If you were in the 1920's-60's there was a great many crap lenses that would impact in the quality of an image. So photographers learned that they needed to spend some good money on glass in order to get predictable photographs. This lesson was so vital that we adopted it as the truth. And it served us well for years but then the 1990's came and we began to see a shift in photography and in manufacturing.

Motorola came up with Six Sigma in 1986 but it began gaining ground in the 90's. So what is Six Sigma?  Six Sigma is a data-driven methodology focused on reducing defects and improving quality, has had a significant influence on the manufacturing of photography lenses.

Prior to its adoption, lens production often suffered from inconsistencies that affected sharpness, alignment, and durability. With Six Sigma, companies like Canon, Nikon, and Sony introduced rigorous process controls and statistical quality measures that minimized variability during production. This led to a dramatic reduction in defects per million opportunities (DPMO), ensuring that each lens met precise optical and mechanical standards.

One of the key improvements driven by Six Sigma was the enhanced consistency in lens elements—particularly in grinding and coating processes. These processes are critical for minimizing aberrations and maximizing image clarity. Six Sigma tools such as DMAIC (Define, Measure, Analyze, Improve, Control) enabled manufacturers to identify root causes of production flaws, from minute deviations in lens curvature to contamination during assembly. As a result, companies were able to maintain tighter tolerances and improve the overall performance of consumer and professional-grade lenses.


The methodology also allowed for more efficient manufacturing, leading to quicker development cycles and the ability to introduce high-quality lenses to market faster. In essence, Six Sigma not only elevated the technical quality of photography lenses but also streamlined the processes that delivered them to users worldwide.

So what do we see today? Chinese manufacturing has begun proving what Motorola was trying to tell us...given the right manufacturing process, and following a significant sigma approach, you can manufacture quality goods at reasonable prices. So now we see a flood of Chinese made lenses that are frankly brilliant. The quality is top notch and the image quality cannot be distinguished from their high priced German and Japanese counterparts.

I am not saying that they have the same character, and I would agree that someone who is used to shooting Leica can tell the difference in character between one lens and another, but in terms of quality, the human eye cannot.

So when does the lens selection matter?  I did tell you that there was one exception to my position that lens quality does not matter....and it is in survivability. Some cheap lenses will give you a great image but will not survive changes in temperature, high moisture environments or a very bumpy ride. But if the build quality is good enough then the lens quality most certainly will be as well. I have yet to see the modern Chinese lenses lack build quality.

Does this mean that everyone who spends thousands of dollars on Leica glass are fools? No. But what it does mean is that you do not need to spend thousands of dollars on Leica glass for the quality of the image. You can get it because you love gear and enjoy the history of the manufacturer and enjoy using it. You do not need a better reason than that. But let's stop saying that we need to spend thousands of dollars to get a quality image. And don't try to do a side by side comparison to pixel peak to prove a point. The fact is that even wide open he difference is minimal and once you stop down there is no difference to speak to.

So buy the glass you want to buy, and if you are worried about the quality of images you are taking then I suggest you pick better subject matter. And next time you marvel at the detail that a lens was able to capture, thank Motorola...they had a larger impact on that image quality than any other company in the world.