CLeW (Cine Lens Wiki), created by Matthew Duclos and presented by Duclos Lenses, is an online reference resource for professionals and enthusiasts in the motion picture industry. Its purpose is to share knowledge and make reliable, up-to-date information about cinema lenses accessible in a user-friendly format. The site covers lens manufacturers, individual lens models, and the features and history of motion picture lens production and use.

Visitors can browse an alphabetically organized lens database, which includes models from manufacturers such as Sigma, DZOFilm, and Cooke. CLeW also offers a Tools & Data section with practical resources, including a macro extension tube calculator for estimating focusing distances when using an extension tube. Other areas include lens-related tools and data, CLeW Grade, help and contact information, and the Cine Pen Archive.

The project welcomes questions and suggestions and aims to foster understanding and appreciation of the art and technology of cinema lenses. Its wiki content is licensed under the Creative Commons Attribution-NonCommercial 4. 0 International license