Carl Zeiss Jena Flektogon 35mm f/2.8 (Part 2)

Back to the future: Part 1

The Carl Zeiss Jena Flektogon 35mm f/2.8 is a classic lens, produced in several versions from the 1950s onwards. The version I own has six elements in five groups and nine aperture blades.

Its imperfections are part of the attraction. I am particularly interested in the way it handles flare and the distinctive out-of-focus highlights it can produce. My copy has good central sharpness wide open and becomes very sharp across more of the frame when stopped down to around f/5.6 and beyond.

I like the way this lens can produce flare. Some photographers regard it as an unwanted defect; I sometimes find that it adds emotion, depth or atmosphere to a photograph. The important distinction is between controlled flare and veiling glare. Distinctive reflections can be used creatively, while a general loss of contrast and colour saturation can weaken the image. In those situations, a lens hood is useful.

Using the Flektogon 35mm f/2.8 with an extension tube

Extension tubes are an application I had previously overlooked, but I have become very enthusiastic about using them. They reduce the minimum focusing distance and allow greater magnification without adding glass to the optical path. The result can be surprisingly good, although you lose infinity focus and some working distance.

This flower photograph was taken handheld and is straight out of the camera, without Photoshop adjustments or cropping.

Several people have suggested using an M42 bellows instead of extension tubes. Bellows offer more flexibility and a wider range of magnification, and they can be found at similar prices on the second-hand market. I bought my extension tube for very little, but if I were paying the full price, a bellows might be the more versatile option. They also look rather impressive.

The basic relationship is that increasing extension increases magnification. The exact magnification and working distance depend on the lens design, focus setting and extension used, so the formulae below are only simplified approximations:

• Magnification increases as extension increases and focal length decreases.
• Working distance generally decreases as magnification increases.

Historical note: This article reflects my experience with one version of the Flektogon and the accessories available to me in 2017.