William Optics Bahtinov Diffraction Spikes mask 75–110 mm (SKU: BM-DS-GR45)

William Optics Bahtinov Diffraction Spikes mask 75–110 mm (William Optics, SKU: BM-DS-GR45) is a mask for precise focusing using a star image. Its pattern produces characteristic diffraction spikes whose relative position indicates focus accuracy.

Key features

• focus assessment using the diffraction spike pattern
• adjustable support points for positioning the mask on the tube

Included items

• focusing mask: Diffraction Spikes Bahtinov 75–110 mm

Technical specifications

• type: Bahtinov mask
• mounting diameter range: 75–110 mm
• application: checking telescope focus

The mask makes repeatable focusing easier before taking astronomical images.