This page shows some of the performance weaknesses of the Voigtlander Color-Skopar 20mm f/3.5 SL ASPH.
The moderate price, small size, and relatively simple optical construction of the 9-element 20/3.5 Color Skopar can’t hope to compete with a highly corrected and much larger lens like the Zeiss ZF 21/2.8 Distagon, with its sixteen (16!) elements. We can expect to see some performance shortcomings with the Color Skopar away from the center of the frame, and it would be unrealistic to expect it to perform as well as more advanced and much larger optical designs.
The solution (as usual) to overcoming optical shortcomings is to stop down, and for the Voigtlander 20/3.5 Color Skopar, f/8 is your optimal choice.
Article continues for subscribers...
If you’re already a subscriber, CLICK HERE TO LOG IN
diglloyd Advanced Photography includes hundreds of pages of exclusive coverage and high resolution, Retina-grade example pictures detailing Canon and Nikon DSLR bodies and their lenses, with in-depth analysis of sharpness and contrast, color, bokeh, vignetting, distortion, MTF, and flare. Also included is a wealth of in-context technique and workflow insight. Since 2006, diglloyd Advanced Photography is the authoritative review and on-line reference for discerning Canon and Nikon shooters. Subscriptions cost $ per year.
Nikon D3x + Voigtlander Color Skopar 20/3.5 @ f/4