Classic Inlay Bahtinov mask for extra large apertures. This mask can be used with many reflectors and refractors.

What are the special characteristics of these mask?

• The Bahtinov pattern will calculated according to your parameters: diameter, focal length. Most other masks on the market are actually designed for larger telescopes with very long focal length and so have a much too coarse pattern
• I use a similar mask with my TS RC8 telescope.

Please select parameters according your needs:

• Tube inside diameter (in mm) where the mask will be placed. Note that a certain tolerance is added to this size so that the mask will fit with certainty. The maximum diameter is 250mm, see other offerings for smaller masks.
• The focal length
• Optionally and if you are familiar with this, or just want to try something out, select an individual Bahtinov factor. By default, the factor of 150 is used
• Custom text to put on the mask. By default, the diameter and the focal length will be used

Due to its large size, this mask is not available with a box. The mask will be made of two parts which are glued together. Some traces of the glue might be visible, but they have no optical influence