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The very basic 4-element Ernostar was Ernemann's variant of Gundlach's fast movie-camera lens Ultrastigmat, replacing the inner biconvex element of that Anastigmat lens with a convex-concave element. This 4-element design was replaced by a five-element construction, replacing that inner element by a cemented 2-element group, giving the Ernostar 1:2.7 known from the Ernemann Klapp-Camera camera - not one of the best lenses.

The famous fast Ernostar was also introduced in 1924 as f2.0 lens for the camera Er-Nox, which soon was renamed to Ermanox.

It could be improved to an even faster lens, the f1.8 85mm Ernostar of 1925. In 1925 this was the fastest available still camera lens.

The asymmetric anastigmat was developed by Ludwig Bertele for Ernemann in a lot of variations, obviously with the ambition to get the best out of four lens-element groups.

speed camera-type elements groups
1:2 (?) cine (?) 4 4 (1-1-1-1)
1:2.7 still 5 4 (1-2-1-1)
1:2.0 " 6 4 (1-2-2-1)
1:2.0 " 6 4 (2-2-1-1)
1:2.0 " 5 4 (1-1-1-2)
1:1.8 " 6 4 (1-3-1-1)

The final f1.8 version gave the model for the Bertele's Sonnar which he developed in 1931 for Zeiss, just reducing the number of goups from 4 to 3, which became the characteristics of the Sonnars: Many elements packed in 3 groups, thus reviving the triplet idea as a triple of groups instead of a triple of elements, including at least one 3-element group. Somehow the Ernostar as well as the Sonnar must have been quite unsatisfying for the developer since both lenses were featured in a great lot of different constructions.