CARL ZEISS JENA VARIO-PRAKTICAR 35-70mm f/2.7-3.5 MC

DE 3602859 A1 — Utz Schneider, Volker Tautz, Karin Holota

9 ELEMENTS / 8 GROUPS
f ≈ 35.0-65.2 mm (DESIGN)
F/2.7-3.67 (DESIGN)
2ω ≈ 63.4°-35.1°
NO ASPHERICAL SURFACES

Focus Mechanism

RECONSTRUCTED, not published: rigid unit extension of the whole powered system against the plane plate that claim 2 fixes to the camera, so only l7 changes (+1.78 mm at 35 mm rising to +6.58 mm at 65 mm for the secondary-sourced 0.80 m object-to-image minimum, solved at each of the ten zoom stations). Eight of those stations are code-solved fixed-image-plane states, not published. The separate 1:3 macro mode at the long end is not modelled.

Optical Elements (9 physical)

ElementTypeGlass
L1Negative MeniscusS-LAL12 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
L2Negative MeniscusLAC13 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
L3Positive MeniscusSF2 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
L4Biconvex PositiveN-SK14 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
L5Negative MeniscusE-FD4 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
L6Positive MeniscusUnmatched (Jena melt, n_e 1.66640 / ν_e 56.14; no verified compatible catalog dispersion)
L7Biconcave NegativeJ-BASF2 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
L8Biconvex PositiveN-SSK5 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed
PPlane-Parallel PlateN-BK7 — compatible native e-line spectral proxy; historical Jena supplier and melt unconfirmed