{"id":2537,"date":"2022-01-04T15:36:11","date_gmt":"2022-01-04T15:36:11","guid":{"rendered":"https:\/\/lensnotes.com\/?p=2537"},"modified":"2022-01-04T15:36:12","modified_gmt":"2022-01-04T15:36:12","slug":"lens-board","status":"publish","type":"post","link":"https:\/\/lensnotes.com\/photography\/lens-board\/","title":{"rendered":"Lens Board"},"content":{"rendered":"\n
\"K.B.Canham<\/a>
K.B.Canham aluminium lens board with Copal 1 shutter hole<\/figcaption><\/figure><\/div>\n\n\n\n

<\/span>What is a Lens Board?<\/span><\/h2>\n\n\n\n

A lens board is a photographic accessory used to attach a lens to a large format camera or an enlarger. Lens boards represent the oldest approach to lens interchangeability in cameras, and as such are a predecessor to contemporary bayonet mount systems. <\/p>\n\n\n\n

Usually made of wood, plastic or metal, lens boards can be found in many different shapes and sizes. A typical lens board represents a flat rectangle or square with a hole in the center, much like the Canham unit above. Some designs may feature locating notches, beveled corners and \/ or stepped edges to fascilitate mounting and light-proofness of the system. The rear (film facing) side of the lens boards are always painted flat black to eliminate any reflections inside the camera body.<\/p>\n\n\n\n

<\/span>How is a lens board used?<\/span><\/h2>\n\n\n\n

There are two stages to using a lens board. When you get a new lens or a new camera, you need to install your lens onto the appropriate lens board. Each one of the lenses you routinely use with your large format camera should be mounted onto a lens board. The mounting procedure is neither fast, nor something you generally want to undertake in the field. <\/p>\n\n\n\n

<\/span>What are standard lens board hole sizes?<\/span><\/h2>\n\n\n\n

Lens boards are universal, and any lens by any manufacturer can be mounted on any board, provided the board is drilled to the necessary size and the lens can physically fit. Because most large format lenses come mounted in leaf shutters, lens board hole sizes are standartized around the shutters.<\/p>\n\n\n\n

Lens board holes may be drilled in the center or offset, depending on the manufacturer’s design. An off-center lens board hole may be used to achieve a preset amount of front standard rise or fall to overcome camera design limitations. For example, Linhof Technika 4×5 boards have the shutter hole located off-center to align the optical axis of the lens with the center of the film plane.<\/p>\n\n\n\n

<\/span>Copal<\/span><\/h3>\n\n\n\n

The vast majority of large format lenses made after World War II are mounted in shutters complying with the Copal<\/strong> nomenclature which is as follows:<\/p>\n\n\n\n