Canon BS-55 (Years not documented)

A 55mm bayonet-mount lens hood for Canon FD shooters who wanted clean, flare-free images from their breech-lock lenses.

Specifications

Manufacturer	Canon
Exact product name	Canon BS-55 Lens Hood
Product type	Lens Hood / Accessory
Size	55mm
Compatibility	for FD 50mm 1.4 SSC and 1.8 SC lenses
Compatibility	for 50mm FD breech lock lenses
Compatibility	for 50mm f1.4 FD Breech Lock
Versions	Plastic and metal versions are available

Key Features

55mm Bayonet Mount Design

The BS-55 attaches with a bayonet mount. That fits Canon's FD system: secure, fast and precise. A slip-on or screw-thread hood can't promise the same consistent alignment, and the bayonet goes on quickly when the light is changing or you're on the move. The 55mm size is reportedly matched to the field of view and shading needs of the FD 50mm lenses it serves, particularly the f/1.4 SSC and f/1.8 SC variants.

Flare Reduction and Image Contrast

The BS-55 is a lens hood, so its job is optical protection. It puts a physical barrier around the front element and blocks stray off-axis light that would otherwise scatter inside the lens and degrade the image. According to available documentation, it reduces flare and improves contrast, which helps keep the crisp, high-contrast rendering FD-series shooters prized. That matters most with fast 50mm primes in mixed lighting or backlit scenes.

Plastic and Metal Variants

Owners report that the BS-55 was made in both plastic and metal versions. No official documentation confirms a timeline or tells the two apart by model. Two materials suggest the production run may have seen cost or supply chain changes, but without verified dates or part numbers that is anecdotal. Collectors note that the metal version feels sturdier and matches the all-metal construction of high-end FD lenses. The plastic one is lighter and may have been a later cost-reduction measure.

3D Printable Reproduction

Someone has developed and shared a 3D printable copy of the original BS-55 bayonet mount lens hood, which points to ongoing demand and a scarcity of original units. The open-source version is used by FD system owners and analog revivalists, particularly those restoring or shooting vintage Canon gear. It is not an official Canon product, but it is a functional replica.