SEVUN: the modular telescope
The first telescope with interchangeable optics
SEVUN invents the truly evolutive telescope.
Lifetime Quality Guarantee
An investment designed to last for decades.
Designed in France
Carefully assembled in our workshop near Bordeaux.
Unprecedented modularity
The only system that adapts to your practice. Compatible with three mirror diameters (150, 200, 250 mm) and up to a 1250 mm focal length.
The traditional market: choosing means giving up.
Until now, traditional telescopes have been fixed in diameter and focal length, forcing astronomers to make an optical compromise at the time of purchase. As their practice evolves, changing configuration requires replacing the entire instrument.
SEVUN: Interchangeable Optics.
SEVUN breaks this constraint by introducing, for telescopes, the equivalent of interchangeable-lens cameras: a single main platform designed to easily accommodate different optical kits, without complexity or questioning the system as a whole. Thus, we offer three mirror diameters—150 mm, 200 mm, and 250 mm—and focal lengths up to 1,250 mm, giving you the power to define your own usage.
Two platforms for an infinity of explorations.
The CORE platform: The Essentials (3.3 kg).
Designed for astronomers who prioritize mobility. The CORE platform is our lightest platform, with a fixed architecture and no telescopic mechanism. This weight optimization improves portability, offering focal lengths up to 900 mm (150 f/6, 200 f/5, and 250 f/4). Ideal for fast, nomadic observing.
Discover CORE →
The ADVANCED platform: Telescopic Exploration (6.8 kg).
Designed for a total optical evolution, the ADVANCED platform integrates a telescopic sliding system. Although slightly heavier, this mechanism is essential to adjust longer focal lengths, up to 1250 mm (150 f/8, 200 f/6, and 250 f/5).
Discover ADVANCED →The SEVUN Optical Kit: The Science of Interchangeability.
Composition and Freedom of Use
This innovation allows you to build your instrument in a modular way, according to your practices and ambitions. An Optical Kit is a complete opto-mechanical assembly, composed of two inseparable modules: a primary module integrating the primary mirror, and a secondary module integrating the secondary mirror, its spider, as well as its two observation stations equipped with focusers. Each Optical Kit mounts directly onto your platform (CORE or ADVANCED), without any structural modification. You may choose to use only one kit, acquire another later, or own several in order to cover different needs in aperture and focal length. The SEVUN platform is compatible with three mirror diameters—150, 200, and 250 mm. Thanks to the integrated sliding system, adjustment is immediate and allows focal lengths up to 1,250 mm, offering optimal flexibility without mechanical complexity.
View all Optical Kits →Optical Modules in Action
CORE platform and optical modules in action
ADVANCED platform and optical modules in action
The SEVUN light shroud
Each SEVUN optical kit is delivered with its textile light shroud and its dedicated structure made of pultruded carbon tubes.
The primary function of this shroud is to block stray light and protect the optical path from the external environment during observing sessions.
It is specifically designed to integrate into the SEVUN modular system and ensure uniform fabric tension, while allowing quick and easy installation.
The light shroud is not an optional accessory: it is systematically supplied with every optical module kit.
Optics and Mounts
Optics
We do not manufacture mirrors. Our standard offering includes GSO optics, which can be ordered directly from our website. For specific requests, we connect our customers with recognized optical craftsmen.
Bare Material: If you have your own mirrors
If you already own your own mirrors and wish to integrate them into our platform, you may order bare optical modules in order to install your mirrors.
Mounts
We do not manufacture mounts; however, we offer a selection of compatible mounts that can be added directly to your order.
Our Workshop
Our workshop is located in Moulis-en-Médoc, in Gironde, France. This is where we ensure the development of our telescopes, the assembly of each unit, optical and mechanical inspections, and the shipment of your telescope.
Each optical system is verified. We perform a star test and a Roddier test on every assembled telescope. These checks are systematically carried out to ensure that the delivered instrument meets our quality standards.
SEVUN Custom Solutions.
SEVUN CORE and ADVANCED platforms cover the majority of uses. However, if your observation or astrophotography project requires a non-standard optical or mechanical configuration (specific focal lengths, integration of highly specific mirrors), we study your request in our workshop.
Contact us to discuss the feasibility of your project.
Request a custom quoteThe Voice of Our Explorers.
I had been looking for my first telescope for many years and had never taken the leap, despite all the options available. Then one day, during a stargazing event, I discovered the Sevunscope, a telescope with the unique feature of being evolutive. The idea immediately appealed to me: the possibility of changing mirror size, the ease of transport… in short, it made me want to discover more. I took the leap during the Kickstarter campaign. I didn’t know exactly what I was getting into, but the idea of such a telescope appealed to me so strongly that I placed this pre-order, which today finally allows me to discover the sky. After several long months of waiting and following the evolution of the Sevunscope adventure, I finally received my own telescope—hand-delivered by Paul and Damien, whom I thank for the immense amount of time they devoted to bringing this project to life. I discovered a playful object that requires assembling the instrument with relative ease. My first adjustments were certainly long, but in the end, observations are now within eyepiece reach. Planetary discovery came first, then the desire to observe more subtle objects followed. At last, I discovered what I had been waiting for all this time: my very first telescope. I find it visually appealing; the materials are high quality and well-crafted. There is a certain weight to it, but to me, that reflects quality. I look forward to evolving this instrument further and sharing beautiful observations. I can only recommend trying an observation and letting yourself be seduced by this beautiful object. A truly innovative idea for lovers of stellar discoveries.
Gaylord T. – Amateur astronomer
They talk about SEVUN.
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