The Birth of the Standard Lens
The original Leica, created in 1914, was the first camera to use film in the 24 x 36mm format. At least three UR Leicas were built by Barnack, who also tried out different lenses, including the retractable Mikro-Summar 42mm f/4.5.
A standard lens is one whose focal length is about the same as the diagonal of the film. For a standard 24 x 36mm format camera, this is about 43mm. In reality, the actual focal length designed by Ernst Leitz for the Ur-Leica seems to be closer to 43mm.
Max Berek came up with the Elmax 50mm f/3.5 lens for the Ur-Leica, which stands for “Ernst Leitz and MAX (Berek).” The 42mm lens was replaced by the Elmax 50mm f/3.5, which offered better optics, in the production Leica I.
Since then, the 50mm lens has become the standard lens, but some companies do offer lenses that are closer to a 43mm focal length, like the Pentax 43mm f/1.9 and the Contax 45mm f/2.
Safe and Comfortable
I’ve always had a soft spot for the compact and collapsible 50mm Elmar f/3.5. I tend to be a bit reserved when it comes to using larger lenses for street photography, but the Elmar’s small size makes me feel at ease. When shooting in well-lit conditions, I typically set the aperture to f/5.6 – f/8, and with an ISO 400 film loaded, I’m ready to go for some serious street photography. Overall, the Elmar’s convenience and reliable performance make it a great choice for my photographic adventures.
Tessar-Type
This Tessar-type lens was considered one of the best of its time, with four elements in four groups. However, it does lose some sharpness in the outer zones when used wide open. However, I’ve found that the Elmar f/3.5 is sharper than the Summar and Summitar when stopped down, even by just a stop or two. The Elmar f/3.5 also has better contrast than uncoated lenses, which tend to have lower contrast and flares. This makes it ideal for black and white photography. The smallest aperture for my collection of f/3.5 Elmars is f/18, except for the last series, which has f/22 and the red scale.
On Digital Ms
You can use the lens with digital Leica M cameras if you get an L39-M adapter. Just a heads-up: collapsible lenses might contribute to sensor dust. I’ve noticed this more often with f/3.5 Elmars. From my experience, the Leica M9 sensor seems to collect more dust than my DSLRs with built-in automatic sensor cleaning.
One possible reason for this is that collapsing or uncollapsing the lens may create a pumping effect that introduces air and dust into the camera mount. To avoid this issue, it’s best not to collapse the lens while it’s attached to the digital M camera.
Personally, I prefer to use non-collapsible lenses on digital M cameras to minimize the risk of sensor dust. If you are concerned about sensor dust, you might want to consider shooting film instead.