What is it about?

UVEX 3 is a complete DiY (Do it yourself) spectrograph project, accessible to all, at low cost (less than 700 € all included), and usable for science in an educational setting or in a ProAm collaboration

The Project is also a team, from left to right, Jean-Luc Martin, Alain Lopez, Pierre Dubreuil, Stéphane Ubaud ….

… and Christian Buil.

The project includes:

  • The design of a complete and light spectroscope, simple to understand in terms of operation, capable of being, installed on a very small instrument. It includes the UVEX unit itself and a CALIBREX calibration and autoguiding unit.

This site is collaborative, dynamic it is a CMS. it allows people to be able to publish articles without entering HTML code. It’s a WordPress

  • A spectro-uvex.tech collaborative website aims to bring together all theoretical and practical information, production in 3D printing, assembly, adjustments, spectral processing and different user experiences.
  • A data base online written in Python which allows UVEX users to compare the quality of the spectra with each other but also compare with spectra from the BESS database. This database is a means of visualization and graphical presentation of spectra


CAD was designed with Freecad v0.18 software which is free and open source CAD software.

UVEX 3 is an operational prototype, already successfully produced with two 3D printers, a K8400 Vertex which is an old model and an MK3 i3 Prusa which is a much more recent and well-known model. This last costs around 800 €, but it is possible to print the box with a cheaper 3D printer or to use the services of a FabLab or a club, a High school. The printing of a UVEX unit takes approximately 12 hours, the CALIBREX 9 hours and the attached parts in a few hours.

The plastic used is PETG, because it is easy to process, it has a low coefficient of expansion and it is as rigid as ABS, we recommend PLA much too flexible. Other plastics can be used but be careful it must be opaque to IR.


  • Compatibility with the Alpy, it is a calibration + autoguiding unit with a 42mm backfocus, should accept a photographic lens like a telescope or a telescope.
  • Compatible with the Shelyak glass slot game and the ALPY base module slot game.
  • Arduino Nano-based electronics that control a Relco standard, neon / argon standard lamp, a small tungsten flat lamp and a modeling booster. The servomotor makes it possible to obscure the field of the telescope during calibration and to return the beam of calib lamps to the slot
  • ASCOM driver   (SpectroNanoAscom) which behaves like a filter wheel. It allows remote control via USB. The ASCOM driver allows you to program the alternation of installation and calibration in software like Prism or MaximDl
  • Direct control software (calibrex Control) which allows remote control if you are not using “all-in-one” acquisition software.


Videos to show all stages of the project


Written in Python on an online Jupyterhub platform.

Enables viewing of star spectra already produced by the UVEX community.

Allows you to upload your own spectra after authentication and compare them with those of the database.

Allows you to compare any spectrum with those of the BESS database

Used to compare a star spectrum with a reference star spectrum.

Allows you to control the wavelength calibration and the correction of the instrumental response.

UVEX database a means of comparing UVEX spectra
UVEX a multiform spectroscope from R = 800 to R = 3000 depending on the configurations.
Identical sharpness from extreme UV to near IR.

This Post Has 2 Comments

  1. Nacho Novalbos

    Great job!!
    I would ask you about if you are developing an INDI driver for the Calibrex?

    Thanks for all.

    1. Stephane Ubaud

      Oui c’est prévu à terme mais il nous faudra trouver un développeur linux.

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