Lenses ~ Steinheil

I wanted to write a little about what I'm experiencing using lenses from a former German manufacturer.  C. A. Steinheil Söhne Optical and Astronomical Works, as they were first known, made early and significant contributions to lenses for photography.

 

Sony A7RII
Steinheil 45mm f/2.8 Cassarit at f/11 

A little history ~ 

In 1866 Carl August von Steinheil patented the Rectilinear four element two group symmetrical design lens.  He beat Dallmeyer by a week or two to the patent.  The importance of this early design can't be over-stated.  Many subsequent designs descend from this idea.

There was also an early design for what would later by patented by Carl Zeiss as the tessar four element three group design.  Steinheil patented theirs in 1881, which was two decades before Zeiss.  Zeiss inverted the Steinheil optical layout and successfully claimed uniqueness of concept before the patent office.

Steinheil continued to develop lenses for photography through the 1960's.  They had Dagor/Protar designs. They offered their Antiplanet inverted tessar.  They developed Cooke triplets.  Many of these lenses are available for not much money on the used market these days.

Soft focus lens search ~ 

I've been looking for lenses that gently introduce optical imperfects into images made on miniature formats.  

Wollensak offered a Velostigmat Series II that allowed users to move the first/front element away from the second and third element and group.  Various focal lengths implemented this feature to be used on various large film formats  The lenses introduce soft focus effects that were sought after by Pictorialists and portraitists at the time.  I am looking for something similar for use on miniature formats.

I stumbled across a Japanese first element focuser, bought one, and found it does the trick, just like the Velostigmat Series II.  Then, a friend alerted me to the fact that certain German lenses from the 1950's and 1960's were also first element focusers.

In these I found the soft focus lenses for miniature formats that I was looking for. 

On vacation ~ 

This past winter we headed to Italy to escape the cold, gray, set skies of Paris, only to have those clouds and wet follow us.  No matter.  We needed to get away.  

I hauled a Sony A7RII with three lenses.  One of the lenses practically lived on the A7RII was a Steinheil 45mm f/2.8 Cassarit.  This is a unit focuser in a m39 Paxette mount (44mm FFD, not the more comment 28.8mm Leica Thread Mount spec).

This unit focusing 45mm Steinheil went along because I'd not correctly/fully cleaned a 50mm f/2.8 Auto-Cassaron Edixa my friend originally alerted me to.  I didn't think the 45mm would have much majick.  I was wrong.  These Steinheils they have a range of soft focus-ness that can be quite useful.

The soft focus images made around Napoli and Rome were made with the 45mm f/2.8 Cassarit unit-focuser. 

Designed differently ~

Steinheil unit and first element focusers seem to share a common trait.  They render very crisply with evident underlying sharpness.  They also exhibit an overlaying reduction in overall contrast and highlight bloom.

Characteristics of two soft focus candidates ~ 

• Ricoh 55mm f/2.2 
• four element four group
• First element focusing 
• ISCO Iscotar 50mm f/2.8 
• Cooke triplet 
• First element focusing
• Both lenses
• Soft wide open
• Good contrast from wide open
• Center sharpening up as aperture closes
• Edges struggling to sharpen up even as aperture closes
• Exposures normal ~ comparable to modern AF optics 
• Highlight bloom diminishes with aperture closure 

Characteristics of Steinheil soft focus candidates ~

• Sharp across from wide open
• Veiling softness at all apertures ~ diminishing slightly as aperture closes
• Tendency to feel over-exposed on Sony mirrorless ~ tonal distribution crowded to the high end of the curve
• Highlight bloom largely unaffected by aperture closure 

Note: I also have a 135mm f/4.5 Culminar 4 element 3 group tessar formula Steinheil lens.  It's not as sharp from wide open as the shorter focal length lenses listed above.  Stopping down does little to improve resolution.  However, there remains the underlying veiling and highlight glow of the two shorter focal length optics.  This is different than how a 135mm f/4.5 Staeble behaves.  The Staeble has good contrast from wide open, which improves with the closing of the aperture.  I'm beginning to think that soft image rendition is a Steinheil trait.  If anyone knows a Steinheil lens designer who wouldn't mind commenting, I'm all ears.

This underscores something I've come to appreciate.  That is, a photographic lens of the same optical layout designed by two different teams can and often do render differently.  Sometimes dramatically differently.

To me this means any majick found in lenses is not simply the result of the lens type (tessar, plasmat, triplet, Ernostar, Sonnar, etc).  Rather, differences in rendering are the result of the calculations and decisions made in details, such as lens curvatures, glass types, and element placement.

 

----------- Resources -------------

Steinheil lenses with design cross-sections 

Steinheil company history