Carl Zeiss Jena Herar 35mm f/3.5

Carl Zeiss Jena Herar 35mm f/3.5

The Carl Zeiss Jena Herar 35mm f/3.5 is a rare pre-war wide-angle made for the Contax system between 1938 and 1939. It has an independent factory identity and an unusual five-element, two-group optical construction.

The optical system consists of a cemented front triplet and a cemented rear doublet. This arrangement reduces the number of exposed air-glass interfaces to four, an important consideration for an uncoated lens produced before anti-reflection coating became universal.

The chrome-finished lens uses the external Contax bayonet and has its own focusing helicoid. It is rangefinder-coupled and focuses to approximately 0.9 metres. The five-blade diaphragm operates from f/3.5 to f/16, while the front accepts 40.5mm filters.

Optical qualities

Rendering

The Herar’s two-group construction was intended to suppress internal reflections without relying on lens coating. It can preserve useful contrast better than its five elements might suggest, although direct backlight can still produce flare and veiling.

At maximum aperture, surviving user comparisons show some residual spherical aberration and gentle transitions away from the plane of focus. Peripheral detail can remain comparatively balanced for a 1930s uncoated 35mm lens, although individual results depend heavily on haze, cement condition and element alignment.

The five-blade diaphragm produces a clearly polygonal opening when stopped down. Background highlights and sunstars can therefore acquire a distinct five-sided form.

At maximum aperture

Maximum-aperture performance should be evaluated with a correctly calibrated camera. A coupled rangefinder measures distance through a mechanical cam and does not inspect the image plane directly. Small errors in the body, mount or lens can therefore shift the sharp plane. Subject movement and field curvature may also be mistaken for optical softness. A clean, properly assembled lens should be tested at several distances before conclusions are drawn.

The widest setting provides the greatest light transmission and the least depth of field available from the design. Contrast can be reduced by residual aberrations, internal reflections or aged coatings. Bright point sources may show glow or flare. These effects vary between examples and should not be presented as a fixed signature of every surviving lens.

Stopped down

Closing the diaphragm increases depth of field and generally improves consistency across the 35mm frame. Middle apertures are often the practical choice for documentary work, landscapes and architecture. The smallest aperture provides more depth but is not automatically the sharpest setting because diffraction gradually reduces fine contrast.

Aperture shape depends on blade count and mechanical condition. Oil, bent blades or an incorrectly assembled iris can change both operation and out-of-focus highlights. Published blade counts should remain tied to the exact barrel version rather than copied between mounts.

Handling and compatibility

Contax and Kiev rangefinder lenses use either the internal standard-lens bayonet or the external bayonet. These interfaces serve different mechanical purposes even though they belong to the same camera system. Similarity to Nikon S or another rangefinder mount does not guarantee correct registration, coupling or infinity focus. A suitable adapter must reproduce the required focusing mechanism and keep the rear assembly clear of internal camera parts.

Historical lenses should not be judged from one sample alone. Haze, fungus, separation, cleaning damage, displaced elements and dried lubricant can alter contrast and focus more than modest design differences. Film choice, processing, digital sensor cover glass and adapter tolerances also influence results. A hood may reduce oblique flare but cannot correct internal contamination.

History

Development and Launch

The Herar was developed as a mechanically straightforward and optically economical alternative within the Contax wide-angle range. Its distinctive solution was to cement all five elements into only two groups rather than use the more complex Biogon or Orthometar arrangements.

Production Evolution

Leitz Photographica Auction records describe a single small production batch made between 1938 and 1939. No confirmed regular optical revision or separate barrel generation has been established.

Special Editions/Variants

Examples in Leica screw mount have been reported, but current evidence does not establish them as a normal factory-production mount. They may represent prototypes, samples or later conversions. M39 is therefore not included in the normalized Mount field until firmer factory documentation is available.

Collector Notes

The Herar should be identified through its 35mm f/3.5 engraving, two-group optical formula, chrome external-bayonet focusing barrel and 0.9-metre focus scale. Dimensions remain Unknown because consistent factory measurements have not been found.

When adapting the lens, check both rear-barrel clearance and rangefinder-cam compatibility. Modified rear components and later conversions are known and should not automatically be treated as factory variants.