Here is a description of the equipment that I’m using for astronomy
Equipment for visual observation
For visual observation sessions, I use two Dobsonian telescopes that I built myself (click on the links to see the construction details).
Eyepieces
I primarily use Televue Ethos eyepieces, which fully satisfy me: 100° apparent field of view, excellent comfort with or without the eyecup, and above all, outstanding quality (sharpness and minimal chromatic aberrations).
Photo equipment
Several setups are used for photography :
Ritchey Chretien CFF 300
- OTA : RC CFF 300 mm (F/D 8)
- Mount : AstroPhysics AP 1100 GTO3
- Reducer/Corrector : AP CCDT67 (F/D 5,4 resulting)
- Camera : Atik 4000M + RAF Atik FW2 (Filtres LRGBSHO Astrodon)
- Focuser/rotator : Integra Gemini 85
- Focuser CFF on secondary mirror
- Lunatico Platypus : focuser/rotator/secondary focuser + heaters
- Atik OAG + GPCam Altair2 for autoguiding
With its long focal length and coma-free field, this telescope is ideal for capturing distant galaxies. Its F/D ratio is quite long but can be reduced using an AstroPhysics CCDT67 focal reducer, bringing the F/D down to 5.4, which makes this setup relatively fast. Mosaics remain possible thanks to the clean field of the Ritchey-Chrétien design.
The optical tube is described in more detail on this page.
For now, I use this setup in “mobile” mode, meaning on a tripod with 24V or 230V power. The goal is to set up an observatory in the Creuse countryside to operate this telescope in a fixed position.
This telescope has a unique feature: it has a “twin brother,” as Christophe has almost the same setup (same tube and same camera). This allows us to combine our raw data to create images with more exposures, which is very useful for deep-sky fields.
Nikon Z8 on StarAdventurer
- OTA : various lenses, but mostly : Nikon 70-200mm F2.8 S
- Mount : Star Adventurer 2 wifi
- Camera : Nikon Z8 (FF 45 Mpix)
For mobile use and especially for long-distance travel, the Star Adventurer is a very practical mount because it is battery-powered and includes a sequencer for controlling image capture. With a classic 200mm photo lens, wide fields are accessible with sufficient resolution (6.1 arcsec/pixel).
It fits well in checked luggage (except for the counterweight, which may be detected by X-ray scanners. I had an inspection in Zambia in 2025, but without any issues).
It can also be used with ultra-wide-angle lenses (less than 20mm) for Milky Way photography, as I did in Namibia in 2025.
Older setups
Televue NP101 automated @ E-EYE – interrupted
- OTA : TV NP101 (non IS) : 101/540 mm (F/D 5,4)
- Mount : AstroPhysics AP900 GTO3
- Camera : Atik One 6 (ICX694) + Atik FW2 (LRGBSHO Astrodon filters)
- OAG Atik + Altair GPCam2 for auto guiding
- Lunatico Platypus : focuser + scope cap + heaters
- Automation : Lunatico Dragonfly
The setup was hosted at E-EYE in Fregenal de la Sierra (Apollo V bay) between 2018 and 2023.
The large nebulae of the Milky Way require a relatively short focal length to capture them in their entirety. Paired with the Atik One camera, the resolution is 1.72 arcseconds per pixel, which also allows for galaxy imaging. The resulting field of view is 150 x 100 arcminutes with an APS-C sensor, enabling the capture of large objects such as the Orion Nebula. Additionally, it is completely free of distortions, making it easy to create mosaics of even larger objects (such as the North America Nebula or Andromeda Galaxy).
This telescope was a collaborative project that I worked on with Christophe, a fellow astronomer. We split the funding for this project (equipment and E-EYE rental) equally. We shared the observing time and exchanged raw data and processing results.
Newton GSO 8 in F/D 5 (1000mm) – sold
This is the telescope with which I began astrophotography. I still have the optical tube, but the mount has been sold. I used it extensively for imaging nebulae in the beginning. I notably took it to the Morvan region for my first outings under a “dark” sky, and I honed my CCD imaging skills with it..
- OTA : Newton GSO 200/1000 mm @ F/D 5
- Mount : Skywatcher EQ6 Goto
- Corrector : Baader MPCC mkII
- Camera : Atik 4000M + RAF LRGB et SHO
- Focuser : Crayford JMI Event Horizon
- 80/600 mm guide scope + PL1-M camera for auto guiding
The 1000mm focal length covers a fairly wide field (80 x 55 arcminutes, or one to two full Moons with an APS-C sensor). The F/5 focal ratio allows for reasonable exposure times but does introduce some coma at the edges of the field, which is partially corrected by the MPCC.
Celestron C11 XLT – sold
This is the telescope with which I explored distant galaxies. I took many images with it in 2011 and 2012, mainly while traveling, lost in the fields of Gatinais, between Montargis and Nemours :). But it also traveled to the Morvan region and Savoie.
- OTA : Schmitt Cassegrain Celestron C11 – 280/2800 mm (ouverture F/10)
- Mount : Skywatcher EQ6 Goto
- Corrector/reducer : 0,63 Celestron (F/D 7)
- Camera : Atik 4000M + Atik FW2 (LRGBSHO Astrodon filters)
- Focuser : Crayford JMI Event Horizon
- Maksutov Guide scope – 1250 focal length + PL1-M camera for auto guiding
With its long focal length, this optical tube is primarily suited for planetary or distant deep-sky imaging. When paired with the focal reducer, the resulting focal length is 1900mm, yielding a field of view of 30 x 50 arcminutes—just enough to fit a full Moon with an APS-C sensor. This makes it relatively well-suited for imaging small galaxies. However, with the reducer, there remains some distortion at the edges of the field, as well as significant vignetting, which limits the effective field of view and the possibilities for creating mosaics.
The tube was modified to allow locking the primary mirror and prevent “mirror flop.” The image quality was decent for its time, though not exceptional (see the image of M101 with the C11, which greatly satisfied me in 2012).
