variation of Bahtinov mask - ATM, Optics and DIY Forum - Cloudy Nights
variation of Bahtinov mask - ATM, Optics and DIY Forum - Cloudy Nights
Amazon.com : Starboosa Bahtinov Mask Focusing Mask for Telescopes - 270 Bahtinov Mask for a Tube Outer Diameter from 268-313mm (10.55" to 12.32") - can be Mounted with Brass Bolt Inside or Outside : Electronics
Amazon.com : Astromania Bahtinov Mask Focusing Mask for Telescopes - FM200mm for a Tube Outer Diameter (OD) from 215mm-260mm - can be Mounted with The Brass Screws Inside or Outside The drawtube :