This photo blog is about the smallest 25 mm wide angle lens made - the Cosina-Voigtlander 25/4.0 Snapshot Skopar lens. I purchased this lens as nearly mint copy online to have a wide angle LTM lens to use with my Leica IIIc camera. I got it for $200 which was a very good deal at the time. I didn't want to spend a lot of money for a LTM lens. I could also use it in combination with my already existing external metal combination Voigtlander 21/25 mm viewfinder (the newer round one model with improved optics than the plastic body predecessor).
The lens is tiny - without hood and caps only 35 mm from rear to front. The lens fits conveniently 39 mm filters - standard diameter size of many Leica M lenses. The small lens size comes with one debit - it has no rangefinder focus coupling. Instead the lens allows quick focus with a click-stop focus ring applying zone focusing: it has stops at 0.7, 1, 1.5, 3 meters, and infinity. I was skeptical when I first tried this lens and afraid to have many out of focus photos - but the opposite is the case - it is very hard NOT to focus correctly with this lens. The wide angle of 25 mm allows a good wide range to be in focus - therefore the lens does only supply a very simple hyperfocal distance scale. More is simply not needed - already at f/4 and a rough estimate of the focus point will nail the focus. Aperture f/8 is a guarantee to have everything in focus. I never used this lens at an aperture smaller than f/11 (meaning f/16 or f/22). I am used to the metric system, so having the distance scale in meters is a benefit to me. It might be a culprit for somebody used to the ft distance scale though which is not printed on the focus ring.
I also like the lens design a lot - both focus and aperture rings are small but can be easily moved. The focus ring has a tiny metal focus tab which has to be used to turn the focus ring. The focus ring does not allow to be turned directly on the ring itself. I personally prefer turning focus rings just on the checkered ring pattern instead of using the focus tab. But I got quickly used to turning this ring by using the tab. The distance locations from minimum focus distance (0.7 m) to infinity are very close next to each other which makes it very easy to quickly move from minimum distance to infinity quickly.
The aperture ring has click half stops from f/4 to f/22 and contains 10 aperture blades.
The lens comes with a small round metal hood which seems to be sufficient to avoid flares from my experience with this lens so far. The round hood can be screwed into the outside lens thread. It has one debit - if a 39 mm filter is attached before the hood ring is mounted, the hood often does not fit outside the attached filter. I sometimes simply push the round hood loosely onto the outside of the filter to allow some flare control.
The Voigtlander metal front lens cap sits both on the metal hood ring or directly on the lens itself. The cap sits a bit better and tighter on the hood ring. The lens has a quite long rear plastic lens cap to allow for the protruding back lens element. Important to hold on to this cap because it is unique for this lens.
The lens is built very well with full metal housing. Only debit as in all of my other Cosina-Voigtlander lenses is the too easily removable black paint. The paint starts to loosen first at the aperture and lens holding rings. The silver metal starts shining through - it does not affect functionality of course but will certainly affect the used lens value just for viewing reasons. None of my black Leica lenses experiences the same issue. I wish Cosina would do a better job with the black paint on their lenses.
The lens performs very good optically. B&W photos turn out crisp and sharp with good contrast. Colors appear with excellent tonality. There is barely any corner vignetting wide open and certainly not at f/5.6 and smaller. Big and often overlooked benefit of this lens is its capability to perform excellent in infrared light. There is no IR hot spot seen at f/8.
Photo above: Cosina-Voigtlander 25/4.0 Snapshot Skopar LTM lens with caps and round lens hood
Photos above: Cosina-Voigtlander 25/4.0 Snapshot Skopar LTM lens from side and rear view
The lens was discontinued over 10 years ago but can still be found as used copy online. The name "Snapshot Skopar" likely refers to its potential usage in street photography due to its fast zone focusing capability. But the lens can be used in far more situations other than street photography. It's a perfect small and light travel companion to get the wide shot (85 grams weight). Cosina made a similar 25/4.0 M-mount lens without the click stops of the focusing ring. There is also the discontinued Cosina-Voigtlander 25/4.0 Color-Skopar M-mount lens which has rangefinder coupling and focusing. It is a bit heavier with 144 grams. Both lenses have 7 elements in 5 groups.
I haven't tested my CV 25/4.0 Snapshot Skopar in combination with my digital Leica M-E 240 yet but will add photos taken in this combination when available. I have only seen that this lens doesn't work well when attached to my Sony A7R - severe corner vignetting with purple colors.
A few example photos of the CV 25/4.0 Snapshot Skopar lens mounted on my Leica M6 with LTM/M adapter and Rollei Infrared 400 film:
Taken in combination with Leica M3, LTM/M adapter, and Ilford PanF+ 50 film:
Taken in combination with Leica M6, LTM/M adapter, and Kodak Porta 160 film:
Cliffwood Beach, NJ - Kodak Porta 160 film