This section restricted to Duclos Staff users.

Known Issues:
CAUTION element behind iris blades is an asphere which is a plastic deposit on the surface of the element. This plastic can be ruined with too much cleaning, avoid when possible. If image blooms, most likely the edges of the asphere are starting to peel up and separate from the element. To confirm, stop down to see if the blooming goes away. There is no remedy and replacements are EXTREMELY rare.
Image shift: If shift is due to loose threads, spray and bake will reduce it.
If shift is due to the iris (will shift on the video collimator when the iris is rotated), this is due to spherical aberration and cannot be corrected. Is inherent in the design of the lens.
Service Manual: Disassembly/Re-assembly

Full CLA: 6-7hrs.
18mm & 25mm had floating element so slightly more time is required for dis-assembly than the rest of the focal lengths.
Element compatibility (T1.3s & T1.4s): 18mm T1.3 & T1.4 elements are the same and can be swapped. confirm housing compatibility first though.
Replace front or rear elements (not mounted) only: 1 hr. ea.
rear elements must be cut from housing and re-potted with epoxy
Strip and re-paint rear housing: +1 hr if getting other service work or 2 hrs if no other service is included. (A full C+L should generally be recommended for S&R of the rear housing.)
Spray and bake threads (teflon coating): +1 hr.
requires full CLA to access
Re-anodize front ring: $50
Image shift:
If shift is due to loose threads, spray and bake will reduce it.
If shift is due to the iris (will shift on the video collimator when the iris is rotated), this is due to spherical aberration and cannot be corrected. Is inherent in the design of the lens. …end of Staff section