25mm

loneranger

Well-known
Local time
10:45 PM
Joined
Feb 14, 2006
Messages
427
I know this is slightly offtopic, but can anyone tell me if the Zeiss 25 ZF is similar in quality to the now legendary 25 ZM?
 
The ZM lens (Leica M mount) is a non-retrofocus or "true" wide angle lens known by Zeiss as a Biogon. The equivalent focal length ZF lens (for Nikon F mount) is a retrofocus or inverted telephoto wide angle, known by Zeiss as a Distagon design. The Biogons are simply better lenses for a number of reasons: much less distortion (pincushion, barrel), better flatness of field, sharper out to the corners. The one disadvantage of the non retrofocus wide angle is the relatively greater light fall off in the corners. This isn't much of a big deal to me. It is a very subtle difference. Also, you can't use a Biogon-type lens on an SLR because the deeply protruding rear element of the lens would interfere with the swing of the mirror.

I hope that helps.
 
Last edited:
I woned the 25 Distagon for the Rollei 3003 back in the 80's and currently have the Biogon for my RF's. The Distagon is equally as good as the Biogon. It's the finest 24/25 for SLR's that I've owned or used.
 
I've had the Biogon ZM for a couple years now, and the 25mm/2.8 Distagon ZF for a few weeks. I use M7s as well as Nikon F3 and F4 and print my own color enlargements. Both Zeiss 25mm lenses are very good, though the Biogon is better in terms of resolution and contrast at wider apertures. The Biogon has more noticable light fall-off in the corners, but it's not bad. It has stunningly good image quality, and very nice Gaussian out of focus rendering which enhances apparent depth of field. Corners are crisp from f/4. In my opinion, the 25mm Biogon is the best wideangle available for 35mm film, period.

The 25mm Distagon is very large and heavy for it's focal length, compared to a 24mm/2 or f/2.8 Nikkor, but handily outperforms them in corner resolution and contrast at every aperture until f/11 when the Nikkors finally catch up. While not as good as the Biogon in corner performance at f/2.8 or f/4, the Distagon is very good indeed, with f/5.6 probably being optimum aperture, though still slightly behind the Biogon in the corners. The Distagon also focuses quite close, without extension rings, going to 1:2.5 reproduction ratio. The Distagon comes with a hood, unlike the Biogon. Out of focus imagery is also very good with the Distagon, with out of focus lights at night showing as almost evenly illuminated disks. F/2.8 and f/4 are very nice aperture for out of focus effects, with slightly soft corners.

I think my 25mm ZF is better than the one 16-9.net compared to the Canon 24mm/1.4 L lens, a test in which a 25mm Distagon shows much softer corner performance than the Canon, on a FF Canon DSLR. Could the Canon sensor or the adapter to the Canon camera have interfered with the Distagon's performance or was it a mediocre sample of the lens? It's too bad they did not test to film with the lenses on camera bodies they were designed for, so I find their results suspect.
 
Last edited:
Last edited:
Back
Top Bottom