Table ronde optique amateur francophone 2026 — recap
The first edition of the Table ronde optique amateur francophone took place on March 4-5, 2026, on the Astro-FR Discord server.
Big thanks to speakers who accepted to prepare and present, to the Astro-FR crew for hosting us, and to everyone who showed up and asked questions.
Slides and videos are being published as they come in. The full archive is here:
→ table-ronde-optique-amateur.fr/archive/2026
Schedule
March 4
- Jean-Pierre Gelabert — Une table à polir les miroirs de télescopes. Building a machine to take the drudgery out of rough grinding, fine grinding and polishing, in a few hours of DIY work. [video]
- Lucas Sifoni — DFTFringe live : un orchestrateur Elixir pour l’interférométrie. An alternative “live” build of DFTFringe, making interferometry a bit more near-real-time. [slides] [video]
- Victor Poughon — Torch Lens Maker: conception d’optiques en Python. An open-source Python library for modeling and designing optical systems, built on PyTorch and differentiable geometrical optics. [slides] [video]
- Alain Spang — Premiers essais avec la fonction de transfert optique différentielle. First results with a differential OTF method: two images of the same star, one with a slightly modified aperture, to evaluate mild instrument defects. [slides] [video]
March 5
- Paul Faÿs-Long — Comment tester des petites surfaces très ouvertes. Traditional methods of testing lose precision on very fast and/or very small surfaces, but a micro-tester can help us. [slides]
- Denis Bernard — Quel avenir pour les sténopés ? Against the usual framing of the pinhole as a primitive, “alternative” film device. [slides]
- Eric Royer — Polissage de miroirs plans. Polishing your own secondary mirrors, drawing from experience making the two flats for his 600mm binoscope. [slides]
- Raphaël Labro — Construire sa lunette astronomique avec du verre bas de gamme. Building an artisanal refractor around a commodity 80/600 achromatic doublet, and squeezing as much as possible out of it. [slides]
Next edition
A second edition will be planned. If you have a topic in mind, whether you’ve never presented before or not, start thinking about a 10 or 20-minute slot. The CFP will reopen on table-ronde-optique-amateur.fr next year.