Extreme ultra-wide lenses can be difficult to design for, and generally there are compromises to be made. This is especially true in a lens as compact as the 12mm f/5.6. However, I think Voigtländer has done a great job balancing image quality with this lens, and overall image quality is on a high level.
Extremely wide-angle lenses tend to have some difficulty maintaining strong sharpness to the corners, and the Voigtländer 12mm also fails to be truly sharp corner to corner. However, I think that the 12mm f/5.6 does a very good job, especially considering the compact size. The lens is very sharp across about 80% of the image frame from f/5.6. Wide open, the edges and corners are soft. Stopping down to f/8 or f/11 brings the edges into good territory, and even the corners can be OK here, though there is some residual softness. In some circumstances, the corners can have a bit of a smeared look as well, but I have found this to not be particularly problematic for my shooting. There seems to be some field curvature as well, so I’ve noticed corners tend to be notably sharper when shooting interiors than shooting sweeping landscapes. Still, the 12mm does get sharper than its 10mm brother in the corners, and provides plenty of resolution for my use across the frame. The shot below was taken at f/8. Click here for a full size image.
Wait, bokeh on a 12mm f/5.6 lens? Yeah, there really isn’t much to talk about here. While there is the ability to slightly blur distant backgrounds when shooting at or near the 12mm’s minimum focus distance, there isn’t much blur to speak of, and certainly not enough to really discuss to quality of that blur in-depth. Out of focus areas look fine, I suppose, but no one is going to buy this lens for bokeh.
Color, Contrast and Chromatic Aberration
One of Voigtländer’s strengths is creating lenses with beautiful color and a lovely contrast profile that features relatively high macro contrast, with lower microcontrast, providing lots of pop without being overbearing. The result is a lovely look that features smooth tonal transitions without compromising overall image contrast. The 12mm follows these characteristics to a tee. I simply love the way my Voigtländer lenses draw for landscape and city shooting.
Lateral chromatic aberration is surprisingly well controlled. There is a slight touch of it visible at the edges without correction, but it’s barely field relevant. A surprisingly good performance here. There isn’t much longitudinal CA to speak of because the depth of field is so deep. However, bright edges have a small amount of purple fringing in very high contrast situations. Overall, the control of color aberrations with the lens is very good for a lens this wide.
Distortion, Flare and Vignetting
Here we reach some of the weaker points with the lens. The Voigtländer 12mm shows moderately strong barrel distortion that is slightly complex, so application of the lens profile in Lightroom or Capture one will be necessary for architecture shooting. The lens also has very pronounced vignetting as a result of the compact nature of the lens. I generally like a bit of vignetting with my lenses, but the Voigtländer 12mm even causes me to click that ‘apply profile’ button and remove much of it in post processing. As a result, the corners will have a bit more noise due to the shadows being lifted. The shot below shows both of these aberrations in their uncorrected state.
After applying the distortion and vignetting profile in Lightroom, both of these are largely corrected, as can be seen below. The only difference between the shot above and below is the checking of the ‘apply lens profile’ box in Lightroom:
The Voigtländer 12mm f/5.6 does perform quite well against bright light, however, with minimal ghosting and very good contrast. This is good since with such a wide-angle lens, the sun will often make its way into compositions, as can be seen in several of the sample images on the next page. The shot below, of course, features the sun quite prominently. Also worth noting is that like most Voigtländer lenses, the straight bladed diaphragm creates prominent 10 pointed sun stars.
In all, the Voigtländer 12mm f/5.6 is an imperfect lens, as most extreme ultra-wide lenses are. However, given the compact size, generally good sharpness, excellent contrast and color and good flare performance, I’ve been overall quite pleased with the image quality of the lens.