The Wide Angle Superstar: Zeiss ZM 15 f2.8 Distagon T* 2.8/15
As Zeiss called it, the 15/2.8 Distagon T* is the wide angle superstar of the ZM series of lenses. The price is crazy, and I am crazy enough to get one after a very very long wait for the lens. As usual there were quite some delays in the launching of this superwide, and there were further delays for it to reach Singapore, where I stayed. Getting impatient, I managed to find one in the eBay and taking risks getting from a German seller that I was not familiar with. The deal was a complete package with the 15/2.8 lens, lens pouch, 72mm centre filter and the very expensive 15mm finder. In the end I got a fair deal considering the purchase price, UPS shipping and the tax.
First glance of the 15mm Distagon actually did not impress me very much. As least the lens does not look that expensive. The old Rolleiflex or Contax SLR 15/3.5 Distagon looks much more impressive with the very protruding front element. For the case of the ZM Distagon, the front element recesses well into the build-in hood and therefore allows a 72mm filter to be used with the lens. It is actually remarkable that the lens can take a filter and therefore a centre filter can be attached for critical light falls off situation or a protective UV filter can be used.
According to Zeiss special glass materials were used and floating element design was implemented. Physically turning the focusing ring I cannot see any movement of the front nor the back element, and therefore was wondering whether the floating elements were resite within the lens. Handling is comfortable as I have been using heavy SLR lenses for many years. The original 15mm finder has bright frame lines but not much space is there outside the frame lines. Finder is very bright, barrel distortion at the edges as usual. Exposure reduction for the centre filter is 1.5 thus you do not loose too much light when it is used.
The focusing and aperture rings have more damping then the made by Cosina ZM lenses.
By looking at the MTF curves I was surprised that the top curve seemed to be slightly better in the centre at f2.8 than that at f5.6, a characteristic that I have not seen before in other designs.
Distortion was a bit disappointing. I was expecting the distortion to be improved over the Contax 15/3.5 Distagon but by looking at the distortion curve worst distortion was about 3.75%, only slightly better than the 4% in the 15/3.5. I guessed probably Zeiss wanted to cater for the space in front of the negative for proper TTL metering.
Light falls off was quite prominent, and apparently Zeiss purposely designed the light falls off in such a way that it would not improve drastically with stopping down. As a result you get consistent light falls off characteristics for different aperture setting and thus the supplied centre filter can be used with consistent results. The 15/3.5 lens light falls off improve with stopping down.
Ideally this lens is best used for architecture or scenery photography. Below is an example of me taking interior under hand held condition with the lens aperture wide open:
I had also taken some photos with the lens outdoor under very good sunlight. When I first saw the distortion curve of the lens I was sort of disappointing at the distortion of 3.75%, which was only slightly better than the old 15/3.5 Distagon of about 4%. So far in practice the distortion did not give me any visible problem yet.
Rollei 35RF, Kodak VC160, 15/2.8 D ZM T*, without centre filter, 14 April 2006
I do hope I have sometime to play with this lens. Anyway I have learnt that super wide angle photography is not straight forward. It is not easy to get a good composition, especially if there are objects in the foreground. Also I have yet to get use to range finder photography where I need to visualise what the lens see through the external finder which I think is not an easy task. Also perspective distortion especially with human face near the edge of the composition is not possible to visualise as in the SLR.
Voigtlander R4M, Portra 400, 15/2.8 ZM T*, without centre filter, 7 July 2013, Buddha Tooth Relic Temple and Museum, f4 1/2, Manfrotto 190B/410gear, 7 June 2013.