Sold my Panasonic 20mm for the 25mm WHAT A DIFFERENCE "wow"

Back when dinosaurs roamed the earth, zoom lenses were virtually non-existent and lenses were designed by guys with slide rulers, Leica established a rep for lenses that offered higher contrast and better elimination of flare, CA and astigmatic distortion than most other lenses of a given focal length. This was a result of a combination of factors, not only in design but in the elements used for construction. Tolerances were very tight. High quality glass and coatings were used. Even the tolerance of the lens mount flange and how precisely the film was kept parallel to the lens contributed to the outstanding image quality of Leica optics.  It was mainly the higher contrast that led to the idea of the "Leica Look".

As the Japanese companies copied Leica designs, to make them cheaper they used cheaper glass and more lax tolerances. The result was many Japanese made lenses for 35mm lacked the "snap" of Leitz lenses, even though the actual design was identical. When Nikon introduced the F series "system 35mm slr" they designed their lenses with the idea of rendering higher contrast than other Japanese makers usually achieved. In some cases, photographers felt the contrast was too high. The result was the evolution of the "Nikon look" helping to drive the F series into the position of the top 35mm slr system for over a decade. This was achieved by using multicoating instead of just single coating, and coating more lens elements when other makers coated only the front element.

Now the higher contrast, lower flare and distortion of higher grade lenses is called the "3D look" (which to my mind reveals the dearth of understanding among a lot of people using cameras LOL). Something as simple as a couple of extra layers of coating can contribute to this. An extra ED element can. Even a tighter tolerance in the alignment of elements (especially on a zoom) can increase contrast enough to give the "3D look".

All this before we even get to in-camera settings and post processing. A lot can go into getting the "look", and saying one doesn't see the difference when comparing photos taken with a different lens, camera settings and PP, and even viewed on a different monitor, is not an accurate assessment.

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Some people operate cameras. Others use them to create images. There is a difference.
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