Farpoint Bahtinov Mask Pro System — ZWO Seestar S50The Farpoint Bahtinov Mask is an ingenious new way to easily focus a telescope. Pavel Bahtinov, a Russian amateur telescope maker and astronomer, created this simple, very intuitive method and the device has universally been named after him: The Bahtinov Mask. Center a fairly bright star and achieve rough focus. Then place the mask over the front aperture of your telescope and take a short exposure. The image of the star will show diffraction spikes.