Safety & Standards – ND5 White Light Solar Filters | Seymour Solar

Safe front-mounted solar viewing for telescopes, cameras, and binoculars

Filter Safety

Seymour Solar, LLC designs and manufactures ND5 White Light solar filters for safe, front-mounted observation of the Sun with telescopes, binoculars, and camera lenses. When properly installed, our filters reduce the Sun’s intensity by a factor of 100,000 (ND5) and block visible, UV, and IR light to safe levels for white-light observing and imaging.

ISO Context

Our products are not eclipse glasses and are not certified under ISO 12312-2 (that standard applies only to handheld or wearable eyewear). Seymour Solar filters are engineered for front-mounted use on optical instruments and achieve optical transmittance levels appropriate for safe white-light solar observation when used as directed.

Critical Safety Guidelines

  • Mount the filter on the sun-facing (front) end of your telescope, binoculars, or camera lens. Never use any solar filter behind the eyepiece or within the optical path.
  • Confirm the filter is secure and cannot be dislodged by wind or touch before pointing at the Sun.
  • Cover or remove the finder scope unless it has its own proper solar filter.
  • Inspect before every use. Do not use if scratched, punctured, delaminated, creased, or otherwise damaged.
  • Never leave an instrument aimed at or near the Sun unattended.

Using Helios Solar Glass® & Helios Solar Film Filters

Follow these steps for safe setup with telescopes, binoculars, or camera lenses.

Before You Begin

  • Verify the filter size/cell design matches your optical tube or lens outer diameter.
  • Allow your instrument and filter to equalize to outdoor temperature for 10–15 minutes.
  • Inspect the filter for any visible defects before each use.

Mounting

  • Slide the filter gently onto the front of the optical tube until snug.
  • Tighten nylon thumb screws evenly until secure (do not overtighten). For single-screw cells, use the supplied felt opposite the screw for even pressure and centering.
  • Verify the fit: the filter must not wobble, fall, or be blown off by wind.

During Use

  • Only observe once the filter is installed and verified secure.
  • For imaging, use manual focus and short exposures; remove the filter only after the instrument is pointed safely away from the Sun.
  • For obstructed or large-aperture reflectors/SCTs, consider an off-axis Helios Glass® filter to reduce thermal currents and improve contrast.

What You’ll See

  • Sunspots (umbra/penumbra), solar granulation/texture
  • Moon’s silhouette during partial/annular eclipses
  • Planetary transits (Mercury/Venus when visible)

Using Hyperion ND5 White Light Solar Film Sheets (DIY)

Hyperion Solar Film is 0.002″ thick, durable, and designed for safe white-light solar observation when mounted securely on the front of your device. Only one intact layer is required.

DIY Basics

  • Cut to size with scissors or a sharp blade; build a front-mounted cell or viewer that fully covers the aperture.
  • For 8″+ Newtonian or SCT telescopes, use an off-axis aperture to reduce thermal currents and improve image quality.
  • Before every use, hold the film to a bright light and inspect for pinholes, tears, or creases. Replace if damaged.

Mounting & Use

  • Affix the film securely in a rigid frame; ensure the assembly cannot come loose in wind.
  • Install on the sun-facing end before pointing the instrument toward the Sun.
  • Never place film at the eyepiece or anywhere inside the optical path.

What You’ll See

  • Sunspots, solar granulation, eclipse silhouettes, and disk motion

Cleaning & Care

  • Glass filters: Clean gently with a soft cloth or tissue and isopropyl alcohol. Avoid abrasive materials or heavy pressure.
  • Film filters/sheets: Do not rub the film surface. Handle by the edges; store flat between clean sheets when not in use.
  • Store all filters in a cool, dry place in their protective packaging.
  • Replace immediately if any damage, creasing, or delamination is discovered.

Downloads

Need Help?

Technical Support: +1 (435) 503-9270
Email: info@seymoursolar.com

Not sure about sizing? See our How to Measure for a Solar Filter. For coverage after purchase, view our Warranty & Returns.