Table of Contents

Cooke S4/i 21mm T2.0

Summary

Cooke S4/i optics offer superb optical and mechanical performance, control of flare, distortion, veiling glare and spherical aberrations at full aperture, with the cam-type focus mechanism allowing for smooth focus adjustments.

Tech Specs

Manufacturer Cooke
Series S4/i
Model -
Focal Length 21mm
Max Aperture T2.0
Min Aperture T22
Format Super 35
Image Circle 30mm
Minimum Focus 9 in.
Focus Rotation 270
Iris Blades 8
Optical Design 12/11
Squeeze none
Front Diameter 110mm
Filter Thread none
Focus/Zoom Rod none
Native Mount PL
Data Protocol Cooke/i
Length 4.5 in.
Weight 1996 g
Body Telescope none
Body Material Aluminum
Focus Drive Manual
Iris Drive Manual
Zoom Drive n/a

History

Country of Origin: UK
Release Date:
Launch Price:
Design Revisions:

Service

This section available only to authorized members. Do not share!

Cooke Data Troubleshooting Guide
Contributed by Matthew Duclos
Cooke S4/i Lens Service Guide
Contributed by Anonymous


This section restricted to Duclos Staff users.

Known Issues:
1. optical core is loose in housing. noticed when tipping lens up and down and optics shift front to back. Collimation will change on the projector. If so, cam follower assembly is either loose or damaged. Tightening or replacement should fix the issue.
2.colliamiton changes not due to loose cam follower assembly. to test put lens on projector and pull/push on front ring of lens (not optics) to see if focus cam retaining ring has become loose or was too loose during assembly at factory (for new lenses).

Service Manual: Disassembly/Re-assembly

Full CLA: 5 hrs.
Enter relevant notes here
Tighten/Secure or Replace cam follower assembly: 3 hrs
skips cleaning the optics but includes re-lubing focus and iris.
does not include accessing iris blades which are inside the optical core.

Loose optical core: replace cam follower assembly 3 hrs.+ part
QUOTE ENTIRE ASSEMBLY, NOT PARTIAL DUE TO FIT ISSUES
Electronic issues: + 1 hr.
DO NOT TEST ON RED CAMERAS! Ribbon cable and resistor board are easily accessed. Circuit board is located under optical core inside chassis, requires dropping out optics to access. add time for swapping parts and investigation process
Re-calibrate data: 1 hr.
…end of Staff section

Notes

Media

cooke_s4i_specification_030623.pdf