Skip to content
Price match 30-day returns* Talk to an astronomer before you buy
Shelyak Optical kit for Sol’Ex spectroheliograph
Shelyak Optical kit for Sol’Ex spectroheliograph
Shelyak Optical kit for Sol’Ex spectroheliograph

Shelyak Optical kit for Sol’Ex spectroheliograph

by Shelyak
SKU SHK-ES0036
$430.00 - $430.00
$430.00
$430.00 - $430.00
$430.00
Price Match Policy!
  • Build a high-resolution solar spectroheliograph
  • Achieves 0.03 nm resolution at 650 nm with 10 µm slit
  • Tunable across the 400 nm to 700 nm visible spectrum
  • Features a 2400 gr/mm holographic grating
  • Includes 80mm and 125mm focal length doublets
  • For the Sol'Ex project proposed and led by Christian Buil
Backordered
Request Stock Alert
Availability Info
FREE Shipping in CONUS
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Shelyak Optical kit for Sol’Ex spectroheliograph

    This optical kit contains the core components to build your own Sol'Ex (Solar Explorer), a 3D-printed spectroheliograph capable of 0.03 nm resolution. The system is designed around a 2400 gr/mm holographic grating and matched doublets with 80mm and 125mm focal lengths, enabling imaging across the entire 400 nm to 700 nm visible spectrum. Following Christian Buil's project, you make images of the Sun as if you had a particularly narrow filter (typically 0.3 Ångström), much narrower than any commercially available filter.

    The Sol'Ex Project: Build a 0.03 nm Spectroheliograph

    The Sol'Ex is a do-it-yourself instrument project that allows you to capture high-contrast images of the Sun's chromosphere. Unlike a standard filter, a spectroheliograph builds an image line by line. It works by scanning the solar disk, isolating a very narrow slice of the spectrum, and reconstructing a complete monochromatic image with the help of dedicated software. Shelyak compares the principle to a photocopier, except that the copy is an image of the Sun, and says you can choose the wavelength anywhere in the visible range.

    Accessible wavelengths include H-alpha, H-beta, sodium, helium and calcium, with high-contrast views of the chromosphere.

    The 2400 gr/mm Grating and Matched Doublets

    This kit provides the four optical elements of the Sol'Ex: slit, grating and lenses. It is fully compatible with the 3D printing files on Christian Buil's website and with the mechanical kits offered by Azur3dPrint.

    • Holographic Grating (2400 gr/mm): A 25 x 25 mm holographic grating (OP0177).
    • Collimator Doublet (80mm FL): A 25.4 mm diameter collimator doublet (OP0176).
    • Objective Doublet (125mm FL): A 25.4 mm diameter objective doublet (OP0181). With the 80 mm collimator, the internal reduction ratio is 125:80.

    The GEN 2 Reflective Slit: 7 µm and 10 µm Apertures

    The kit includes the new GEN 2 reflective slit (SE0289), with two positions, 7 and 10 µm wide and 6 mm long.

    Resolution is 0.03 nm at 650 nm with the 10 µm slit; the 7 µm position is narrower.

    DIY Assembly and Telescope Matching at 450mm

    This is a kit of optical components only. You source the 3D-printed parts (STL files are on the Sol'Ex website, or Azur3dPrint offers mechanical kits) and the other components such as cameras and adapters. The project website gives the practical details for building and using the instrument in the field.

    Sol'Ex should be mounted on a small telescope, with a focal length of 450 mm maximum, to see the whole Sun in a single image. A longer focal length is possible and gives more detailed images of portions of the disk.

    From Sol'Ex Solar to Star'Ex Stellar Spectroscopy

    Once you know your Sol'Ex, it can be turned towards other stars: Sol'Ex was transformed into Star'Ex (Star Explorer), a small very high resolution spectrograph.

    Transforming your Sol'Ex into a Star'Ex requires a few additional optical components. These are in the separate Star'Ex HR complementary optical kit (ES0037). You can also choose the Star'Ex HR optical kit, which holds everything to build a Sol'Ex and then turn it into a Star'Ex HR.

  • Does the Shelyak optical kit include the 3D-printed parts for the Sol'Ex?

    No. This kit contains only the four optical elements: the grating, slit, collimator lens, and objective lens. You source the 3D-printed parts and the other components (cameras, adapters and so on) yourself. The STL files for printing are available on the official Sol'Ex project website.

    What kind of telescope is required for the Sol'Ex spectroheliograph?

    The Sol'Ex is designed for small telescopes. To capture the entire solar disk in a single image scan, use a focal length of 450mm maximum. You can use a longer focal length telescope, which will provide higher magnification views of smaller sections of the Sun.

    How does the Sol'Ex 0.03 nm resolution compare to a standard H-alpha filter?

    Sol'Ex images look as if taken through a particularly narrow filter (typically 0.3 Ångström), much narrower than any commercially available filter, giving high-contrast views of the chromosphere.

    What can I observe in H-alpha with a Sol'Ex on a 400mm focal length refractor?

    With 400mm of focal length, under Shelyak's 450mm maximum, the whole Sun fits in one image. Tuned to hydrogen-alpha (656.3 nm), you see chromospheric features such as prominences at the limb, filaments on the disk and bright plage.

    What is the difference between the 7 µm and 10 µm slits on the Sol'Ex GEN 2 slit?

    The slit width determines the instrument's resolution. It reaches 0.03 nm at 650 nm with the 10 µm slit. The narrower 7 µm slit lets less light through.

    Is software included for processing the Sol'Ex solar scans?

    Yes, the Sol'Ex project includes dedicated, automatic image processing software. The result appears on screen in just a few clicks. The software comes from the Sol'Ex project, not with this kit.

    What kind of cameras are needed to complete the Sol'Ex build?

    Shelyak does not name cameras; cameras are among the components you source. See the Sol'Ex project website for the camera choice.

    How do I upgrade my Sol'Ex to a Star'Ex for stellar spectroscopy?

    The Sol'Ex is designed to be convertible into a stellar spectrograph called Star'Ex. This requires a few additional optical elements, in Shelyak's separate Star'Ex HR complementary optical kit (ES0037). This allows you to use the same core instrument to analyze the spectra of stars.

    What safety precautions are necessary when using the Sol'Ex with a telescope?

    Warning: Never look at the Sun directly through a telescope or the Sol'Ex instrument. Follow the instructions on the Sol'Ex project website.

  • Resolution at 650 nm 0.03 nm (with 10 micron slit width)
    Wavelength Range 400 nm to 700 nm
    Internal Reduction Ratio 125:80
    Grating Holographic, 2400 gr/mm, 25 x 25 mm
    Slit GEN 2 reflective, two positions, 7 and 10 µm wide, 6 mm long
    Collimator Doublet, 25.4 mm diameter, 80 mm focal length
    Objective Doublet, 25.4 mm diameter, 125 mm focal length
    Telescope focal length 450 mm maximum to image the whole Sun in one frame
    Resolving Power (R) 0.03 nm @ 650 nm (10 µm slit)

    • Collimator doublet, 25.4 mm diameter, 80 mm focal length (OP0176)

      × 1

    • Objective doublet, 25.4 mm diameter, 125 mm focal length (OP0181)

      × 1

    • Holographic grating, 2400 gr/mm, 25 x 25 mm (OP0177)

      × 1

    • GEN 2 reflective slit, 7 and 10 µm wide, 6 mm long (SE0289)

      × 1

  • Shelyak 1-Year Warranty