Version | Serial no | Date | Screws | Engraving | Notes |
---|---|---|---|---|---|
Ai | < 104143 > | - | 5+ | LMIJ | Prototype shown on instruction sheet with different serial number. Appears identical to production lens. |
Ai | 1760201 < 1760632 � 1775022 > | Jan77 - | 5+ | LMIJ | Thick rear protector, long projection from max aperture post. Start serial number from F601 service manual |
Ai | < 1776176 � 1785355 > | - | 5+ | LMIJ | Thin rear protector, long projection from max aperture post. |
Ai | < 1785006 � 1798041 > | - | 5+ | MIJ | Thin rear protector, long projection from max aperture post. |
Ai | < 1799123 � 1954294 > | - Sep81 | 3+ | MIJ | Thin rear protector, no projection from max aperture post. Somewhere around 186xxxx the aperture coupling prong was made from thinner pressed sheet metal. |