SCHACHT TRAVENAR 90mm f/2.8 — Optical Cross-Section & Ray Tracing

Home / Lenses / Schacht / SCHACHT TRAVENAR 90mm f/2.8SCHACHT TRAVENAR 90mm f/2.8US 2,721,501↗ — Ludwig Bertele
4 ELEMENTS / 3 GROUPS
f = 90.012 mm (modeled)
f/2.8
28° FULL FIELD
ALL-SPHERICAL
Focus MechanismNO_INTERNAL_RECONSTRUCTION — manufacturer literature specifies 1 m to infinity, but no internal finite-focus spacing law is published; the fixed patent prescription is retained without focus var.
Optical Elements (4 physical)ElementTypeGlass
L1Positive MeniscusBAF10 / S-BAH10 class (supplier unconfirmed)
L2Biconvex PositiveUnmatched (nd=1.56536, nu_d=55.8; nearest BAK4/BAL14 family outside delta-n=0.003)
L3Biconcave NegativeSF8 / S-TIM28 class (supplier unconfirmed)
L4Positive MeniscusSF10 / ZF4 / FD10 class (supplier unconfirmed)

Element	Type	Glass
L1	Positive Meniscus	BAF10 / S-BAH10 class (supplier unconfirmed)
L2	Biconvex Positive	Unmatched (nd=1.56536, nu_d=55.8; nearest BAK4/BAL14 family outside delta-n=0.003)
L3	Biconcave Negative	SF8 / S-TIM28 class (supplier unconfirmed)
L4	Positive Meniscus	SF10 / ZF4 / FD10 class (supplier unconfirmed)