Farpoint Bahtinov masks are one of the best tools for manual focusing of your telescope available for astrophotographers.
In 2005, Pavel Bahtinov, a Russian amateur telescope manufacturer and astronomer, detailed a new way to focus your DSLR, CMOS, or CCD camera for astrophotography by adding a mask that matches the diameter of your telescope.
Bahtinov mask is a cost-effective way to focus on objects in the night sky compared to a standard motor focuser.
With the right mask and setup, its easy to get a crystal clear focus on a star in less than 90 seconds.
How it works:
This mask works just as well at the end of a scope or at the end of a dew guard on which the mask itself does not need to be perfected. This is due to the angle of the slots themselves. Choose a bright star as a guide object. Place the Bahtinov focusing mask on the lens of your telescope and attach it with the rubber straps. The slots in the mask design create a series of diffraction tips on the star that help with the accuracy of your focus. It appears on your screen or computer as "X" with a line through the center (when focusing).
The diffraction spike pattern of a bright star wearing a Bahtinov mask. When you adjust the focus of your telescope, the center spike moves in and out of the X pattern. When using the capture software, make sure you compensate for the delay time between exposures on the screen, usually 4-5 seconds. The same process applies with live view display on your DSLR camera.
At Farpoint Astro we are a California-based manufacturer of astrophotography filters, scopes and tools. Our Bahtinov masks are of the highest quality in astronomy space.