Canon FL Mount - Breech Lock 35mm Film SLR Lens Mount

The Canon FL lens mount replaced the Canon R lens mount in 1964 with the release of the Canon FX camera. The FL mount would be used until 1971 when it was replaced by the compatable Canon FD lens mount.

The R mount is similiar to the FL and FD mounts, but the aperture control mechanism is different, even though the lenses will mount onto the FL or FD mounts. That does mean the R mount lenses will work with the same adapters that will allow you to use a FL lens on a modern mirrorless camera.

The Canon Camera Museum has a information on all the FL lenses that were made by Canon. That list was used as a reference for the table below.

There were also some FL mount lenses that were made by third parties. Tamron made an Adaptall lens adapter that will allow Adaptall lenses to be used on Canon FL camera bodies.

Breech Lock

The breech-lock mechanism consists of a ring around the lens mount that can be rotated to lock or unlock the lens onto the camera body.

When attaching the lens to the camera body, the lens is first inserted into the lens mount and then the breech-lock ring is rotated to secure the lens in place. This mechanism provides a secure and tight fit for the lens, preventing any unwanted movement or shaking while the camera is in use.

To remove the lens from the camera body, the breech-lock ring is rotated again to unlock the lens, allowing it to be easily removed from the mount.

Breech-lock mechanisms were used in SLR cameras during the 1960s and 1970s, and were popular for their secure attachment and easy removal of lenses.

Other camera mounts that used a breech lock:

• Mamiya RB (Medium Format Film)
• Canon FD (35mm Film)
• Contax G (35mm Film)
• Petriflex (35mm Film)
• Bolix Bajonet (16mm Film)
• Kowa Six/Super 66 (Medium Format Film)
• Pentacon Six (Medium Format Film)

Breech Lock vs Bayonet

The breech-lock and bayonet mount are two common mechanisms used to attach lenses to cameras. Here are some differences between the two:

1. Attachment mechanism: In a breech-lock mount, the lens is inserted into the mount and then secured by rotating a ring to lock it in place. In a bayonet mount, the lens is aligned and then twisted into place on the camera body. Bayonet mounts typically provide a quicker and easier attachment process compared to breech-lock mounts.
2. Size: Breech-lock mounts tend to be larger than bayonet mounts due to their construction. This can make breech-lock mounts less practical for smaller cameras.
3. Security: Both mount types provide a secure attachment for lenses, but the breech-lock mechanism tends to be more secure due to its ability to tightly clamp the lens in place. However, bayonet mounts are typically more durable and resistant to wear and tear over time.
4. Compatibility: Breech-lock mounts are usually not interchangeable with other mounts, while bayonet mounts can be designed to fit a variety of camera bodies and lenses. This makes it easier to switch lenses between different camera systems, which can be useful for photographers who use multiple camera brands.

List of Canon FL Lenses

Canon made a total of 33 different FL lenses. Different versions of lenses are counted as unique lenses.

The Canon FL 19mm f/3.5 is a short focus lens. The rear of the lens goes back into the camera body and will hit the mirror. As such it can only be used in camera models that have mirror lock-up functionality. (FP, FX, FT, F-1 (old), Ftb, and EF)

The Canon FL P 38mm f/2.8 can only be used on the Pellix and Pellix QL cameras.

The Canon FL M 50mm f/3.5 is a macro lens. In order to reach 1:1 magnification, the correct extension tube needs to be used.

The Canon FL M 100mm f/4 is a bellows lens. It does not have a focusing ring. Focusing is meant to be controlled by mounting the lens onto a bellows.

The Canon FL-F 300mm f/5.6 and 500mm f/5.6 have flourite lens elements.

Complete List of Canon FL Mount Lenses