Bahtinov Focus Mask for MiniGuide Scope

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A Bahtinov focus mask for the QHY MiniGuide Scope. I found focusing this guide scope a bit of a pain due to the threaded focus mechanism. While I could eventually dial in sharp stars, this took quite a while for me at the scope before my imaging sessions. To overcome this and make it a quick process, I decided to try a Bahtinov mask designed for the small aperture (30mm) and focal length (130mm). To focus using the mask I slew to a bright star (Vega works well) and loop my images at 3 sec exposure times. This usually provides a diffraction pattern that is well defined once zoomed in on the star. Should you find the diffraction pattern too small, try a brighter star and/or longer exposures. You could also try increasing the gain of the camera.