Daystar White Light Solar Filter

ISO 12312-2 Certified Solar Safety

Engineered for direct observation of the Sun, this filter uses Thousand Oaks Solarlite film that meets the transmission and quality requirements of the ISO 12312-2:2015 international safety standard. The ND 5 rating ensures that 99.999% of the Sun's intense light is blocked, rendering a detailed and comfortable view of sunspots and granulation in a pleasing warm yellow-orange color.

The film itself has a naturally billowy appearance; ripples or creases in the film do not impact image sharpness. While small pinholes are rendered safe by the black polymer base beneath the metallic coating, care must be taken to prevent punctures or tears that would compromise safety.

Durable Metal Cell with 3 Nylon Thumbscrews

Unlike basic plastic or cardboard filters, this model features a robust metal cell that protects the film and provides a secure fit. The filter is held in place by three glass-filled nylon thumbscrews, which are significantly stronger than standard plastic screws and will not mar your telescope's finish. This secure, three-point attachment system ensures the filter cannot be accidentally dislodged during observation.

Selecting Your Filter: Sizing for ODs up to 324mm+

Choosing the correct size is critical for a safe, secure fit. These filters are sold by their inside diameter (ID). To find your size, measure the outside diameter (OD) of the front of your telescope, dew shield, or binoculars, then purchase the next largest available filter size. For example, if your instrument's front has an OD of 121mm, you should select the 130mm filter model.

Note that very large filters, from 324mm and up, are designed as off-axis, reduced-aperture filters. This design is specifically intended to reduce thermal effects and air turbulence in large Schmidt-Cassegrain telescopes while still providing excellent views.

Film Filters vs. Universal Lens Filters: Durability and Sizing

This filter represents a middle ground between entry-level and premium solar filters. Its primary advantage over more affordable options is the durable metal cell and wider range of available sizes.

• This White Light Film Filter: Features a sturdy metal ring for enhanced durability and protection of the film. It is available in a vast range of sizes to fit nearly any telescope.
• Universal Lens Filters: A more affordable alternative, these are available in 50mm, 70mm, and 90mm apertures. They prioritize cost-effectiveness and are suitable for smaller instruments where the robust construction of a metal cell is less critical.