Open Sonnar

youmagine

One of the most striking aspects of digital fabrication is its ability to rescue timeless creations from the shadows. Our reality owes a debt of gratitude to countless brilliant minds who have worked tirelessly over the years, but often their remarkable achievements are reduced to mere relics or footnotes due to the passage of time and technological advancements. Fortunately, 3D printing makes it possible for us to breathe new life into these forgotten artifacts, allowing them to compete with modern innovations on equal terms. I'm not an expert in photography, but after taking a closer look at the photos above featuring the *Carl Zeiss Sonnar 50mm 1:1.5* lens, I suspect that this vintage gem is one of those rare objects worth reviving. The lens itself dates back to the early 1930s and boasts an impressive combination of robust metal construction and optically flawless glass in a *Sonnar* arrangement – a designation that refers to the precise placement and number of glass elements responsible for focusing light, known for producing a sharp-but-painterly image quality. What's more, this unique arrangement has never been replicated on modern DSLR cameras due to technical limitations. However, unlike modern lenses, this vintage masterpiece was designed to be used in conjunction with a camera featuring an integrated focusing mechanism built into the body, rather than within the lens itself. This means that adapting it to a mirrorless digital camera requires specialized and expensive adapters. The good news is that I've managed to create a sleek, 3D-printable integration between this lens and modern Sony NEX / E-Mount cameras. This design serves as a solid starting point for developing a more comprehensive series of focusing adapters for various lenses and demonstrates the feasibility of creating 3D printed lenses in their entirety. This adapter features a single-helicoid focusing mechanism, which enables the lens to rotate as it focuses. While I've also designed a double-helicoid mechanism, printing it with good results remains a challenge at this point. The focus range is roughly 30cm to infinity, allowing for a wider range of creative possibilities than traditional adapters would permit. I'd like to extend my gratitude to the individuals who have contributed to the success of this project, including those who have provided valuable feedback and suggestions. This adapter has undergone significant improvements since its initial release, with notable updates including: * A 3D printer-optimized threadform that minimizes jerk in the printhead during printing * A finer thread pitch and longer focus throw for closer focusing and easier micro-adjustments * A spring-loaded section of threads that preload the helicoid and eliminate the need for a screw to function as a focus range limiter * Improved light baffling on the inside of the lens mount * A better snap-fit for inserting the lens * A more precise fit for the E-Mount While there's still work to be done, I'm excited about the progress made so far and look forward to continuing to refine this design. One area that requires further attention is dialing in the perfect infinity focus stop, as the current setup focuses slightly past infinity.