Astro Focus Filter for Stars & Planetary Photography

Star Focus Filter helps astrophotographers achieve precise star focus quickly and reliably. Focusing in complete darkness is one of the most challenging parts of astrophotography, as stars are often too dim for accurate manual focusing. This filter uses a built-in Bahtinov Mask diffraction pattern. When placed in front of the lens and pointed at a bright star, it generates diffraction spikes that shift as you adjust focus. When the spikes become perfectly symmetrical, you reach critical focus. Designed for field use, it features an 82 mm front thread and high-clarity optical acrylic construction. CNC-machined aluminum adapter rings (49–77 mm included) ensure wide compatibility. The lightweight design makes it easy to carry and use on any shoot.