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Focus. How to use the Bahtinov mask?


To ensure perfect accuracy, point the eVscope to a bright star and use the Bahtinov mask to adjust the focus.


The Bahtinov mask is included in the cover. In order to use it, please remove the mask from the cover and install it on the eVscope, as in the pictures. Don't be afraid to push it a little bit.

Here’s how to adjust the focus with the mask:

  1. Install and align the eVscope.
  2. In the catalog of your app, select a bright star (ex. Polaris), and ask the eVscope to go to it.
  3. Wait for the eVscope to reach its target.
  4. Put the mask on top of the tube. This will create a specific pattern, with a central line and two other lines forming an X, visible in the eyepiece, or on your smartphone.
  5. If the pattern is too dark, adjust the gain and the exposure time to make it brighter.
  6. Slowly rotate the focusing wheel until the central line is positioned exactly in the middle of the X.

In these three images, you can see a star observed with the mask: In the first two images, the focus was not right. By slowly rotating the focusing wheel, the perfect focus was achieved as shown in the last image.




When the focus is really sharp, if you zoom in, you can see a clear dot in the middle of the X:



 And here is our video that covers the subject:


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