Introduction

When it comes to choosing a 50mm lens for the Leica M system, there are numerous options.

I myself decided to go with the Zeiss C Sonnar 50mm f/1.5, until Voigtlander tempted me with their new Nokton 50mm f/1.5 Asph. II.

Comparison

Weight & Size

The Zeiss C Sonnar weighs 250g and is therefore slightly lighter than the Bicolor version of the Voigtlander Nokton II(255g). The black and silver version of the Voigtlander Nokton II weigh 198g (and lack the brass .

In terms of physical size, the Voigtlander is a little bit smaller than the Zeiss.

The Zeiss C Sonnar 50mm f/1.5 and the Voigtlander Nokton 50mm f/1.5 Asph. II side-by-side

Build Quality

Both lenses are made by Cosina in Japan and are of equally very high quality.

Ergonomics

The Zeiss C Sonnar 50mm f/1.5 and the Voigtlander Nokton 50mm f/1.5 Asph. II top view

The Zeiss C Sonnar has a focusing bump which the Voigtlander Nokton II is missing. Although a matter of preference, the focusing bump is very useful for quickly adjusting certain focusing distances.

The aperture rings are very similar, but it is noteworthy that the Zeiss allows for 1/3 steps, while the Voigtlander only allows 1/2 steps. Again, a matter of preference.

The focusing ring on the Zeiss offers less resistance than the Voigtlander.

Optical Qualities

Focal Length Differences

The Voigtlander has a barely noticeable wider angle of view than the Zeiss.

Close Focusing Distance

The Voigtlander Nokton II has a close focusing distance of 0.7m, while the Zeiss Sonnar C can only focus down to 0.9m. This does not seem to be much of a difference on paper, but when shooting portraits, this is quite significant.

Sharpness

Both the Zeiss and the Voigtlander have very distinct optical qualities. The new Voigtlander uses aspherical lens elements while the Zeiss has none. As a film shooter, I decided to shoot the following basic comparison on Kodak Portra 160 and a tripod. I was quite surprised by the results, as I did not expect such a clear difference: The Voigtlander is significantly sharper throughout all apertures – even on film. The Nocton II also offers better micro-contrast.

While this makes the Voigtlander the better lens in technical terms, the Zeiss might be preferable for portraiture and for replicating a vintage look.

Looking at small prints (10x15cm), the differences in sharpness and micro-contrast are not noticeable.

Bokeh

I am not overly critical when it comes to bokeh and I think that it can be overhyped, especially as it is usually not the out of focus areas but the in focus areas that make for a compelling picture.
To describe the difference between the two lenses, I’d say that the Voigtlander’s bokeh is more “swirley”. Just take a look at the sample images.

Focus Shift

There is one well-known “issue” with the Zeiss Sonnar C, and that is its focus shift. While some degree of observable focus shift is present in almost every lens, it is quite more significant in this one. It caused me to miss critical focus when shooting portraits from aperture ranges from f/1.5 to f/2.8.

I could not find this flaw in the Voigtlander.

Colour Rendition

There is a small difference in colour rendition but it is difficult to say whether this stems from differences in light transmission or the differences in micro-contrast.

Conclusion

On paper, the differences are much more apparent than in everyday use.

Although the Voigtlander Nokton II outperforms the Zeiss Sonnar C in regards of optical quality, the latter still has its merits if you are after its unique vintage look.

I myself decided to keep the Voigtlander and sell the Zeiss. The focus shift of the Zeiss can be quite annoying and I don’t like when equipment leads to missed shots. The (in my eyes) more pleasing bokeh, better optical performance and closer focusing distance of the Voigtlander are the icing on the cake.

Voigtlander Nokton 50mm f/1.5 Asph. II vs. Zeiss C Sonnar 50mm f/1.5