CANON FL 85-300mm f/5

US 3,377,119 A, sole example — Eiichi Takano

15 ELEMENTS / 9 GROUPS
DESIGN f = 87.74–292.45 mm
DESIGN F/5
ALL SPHERICAL

Focus Mechanism

Finite focusing is not modelled: no group moves with the focus control, and both focus states repeat the infinity spacings. Canon publishes a 4 m minimum focus distance but no numerical focusing travel is supplied here. The zoom model retains the three published stations and their rounding; movement between them is calculated, including the compensator reversal, rather than a published factory cam.

Optical Elements (15 physical)

ElementTypeGlass
L1Negative MeniscusFF5 (HOYA catalog equivalent; production supplier unspecified)
L2Biconvex PositiveS-FSL5 (OHARA catalog equivalent, printed νd 70.0; production supplier unspecified)
L3Positive MeniscusS-FSL5 (OHARA catalog equivalent, printed νd 70.0; production supplier unspecified)
L4Negative MeniscusLAC8 (HOYA catalog equivalent; production supplier unspecified)
L5Biconcave NegativeLAC8 (HOYA catalog equivalent; production supplier unspecified)
L6Positive MeniscusFD60 (HOYA catalog equivalent; production supplier unspecified)
L7Plano-Concave NegativeBACD16 (HOYA catalog equivalent; production supplier unspecified)
L8Plano-Convex PositiveE-F2 (HOYA catalog equivalent; production supplier unspecified)
L9Biconvex PositiveK10 (SCHOTT catalog equivalent; production supplier unspecified)
L10Negative MeniscusE-FD4 (HOYA catalog equivalent; production supplier unspecified)
L11Negative MeniscusBACD14 (HOYA catalog equivalent; production supplier unspecified)
L12Biconvex PositiveFC3 (HOYA catalog equivalent; production supplier unspecified)
L13Negative MeniscusE-FD4 (HOYA catalog equivalent; production supplier unspecified)
L14Biconvex PositiveKF8 (SUMITA catalog equivalent; production supplier unspecified)
L15Biconcave NegativeS-FSL5 (OHARA catalog equivalent, printed νd 70.0; production supplier unspecified)