• Place the mask on the telescope and point it at a bright star.
• Turn on the camera and observe the constellation on Live View or on your computer.
• If the image is not exactly in focus, the central line is shifted. Adjust the focuser until the central line runs exactly through the center of the star.
• You have now achieved optimal sharpness. Remove the mask from the telescope and you can begin exposing the image.

Practical tips from Astroprints

• Focusing with a Bahtinov mask is suitable for deep sky photography in the focus of the telescope or with a camera lens. Correctors and Barlow lenses can be used.
• Use a star of medium brightness for focusing; it should not be too bright but also not too dark. The reflection lines must be clearly visible.
• The star should not be exactly in the center, as the image field of the corrected telescope or lens is often not 100% flat. Choose a star in the outer third of the field. This will give you better average sharpness for the entire image.

Technical Data:

Scope of Delivery:

• Bahtinov Maske