Hermagis Paris Hellor 150/45 - is it a good lens?

[renes]

I do not own yet Vade Mecum lens colector and did not found much info about this Hermagis lens by google too. Hope someone from forum members had/have it and can answer if its a good lens, what image is giving, how the lens is build (formula) and how it compares to Heliar 150/4.5. It's Hermagis, so should be very good.

Thanks

[Steven Tribe]

This is a late tessar clone - looks like a bread and butter objective for the mass german folder market. Very different from the heliar. Hellynx is the Hermagis which apparently is nearest the heliar in design and function. (Data from VM).

[renes]

Thanks Steven.

[retrofocus]

Hi, once every 13 years it's important to discuss the design of Hermagis Hellor. Does this really count as Tessar?


Br
Vesa

[David Lindquist]

Hi, once every 13 years it's important to discuss the design of Hermagis Hellor. Does this really count as Tessar?


Br
Vesa

I think so. The concave surface of the rear doublet - the surface facing the diaphragm - looks more deeply curved than what I generally see in drawings of the Tessar but that surface in the Tessar is concave too.

Rudolph designed the Tessar by combining the front of his Unar and the rear cemented doublet of his original Anastigmat (Protar), not by adding an additional element to the Cooke Triplet as is occasionally said, see: https://lenspire.zeiss.com/photo/app...mes-tessar.pdf

In the rear cemented doublet of the original Anastigmat (Protar), the surface facing the diaphragm is more deeply concave than that surface in the Tessar.

In A History of the Photographic Lens (Academic Press, 1989), Kingslake includes the Hermagis Hellor among the lens names that were constructed according to the Tessar formula.

David

[J. Patric Dahlen]

It's a Tessar type lens, which means that it's of similar construction as the Tessar, but might use slightly different curvatures of the lens surfaces and different glass.