TS Optics Bahtinov mask for astrophotography - suitable for diameters from 85-120mm
The Bahtinov Mask is named after its inventor Pavel Bahtinov. This
focusing tool enables precise adjustment of all cameras, e.g. DSLRs,
CCDs or Astro-cameras.
Attaching the Bahtinov Mask to your telescope or lens is very simple.
Each mask is supplied with 3 screws. Remove the plastic from the screws,
put them through the designated holes and then pull the plastic covers
back over the screws. Now you can attach the focusing mask to your
telescope or lens and start focusing.
Attach the mask to your telescope and slew the telescope to a bright star.
- Ideally you want to use a star with medium brightness for focusing. It should neither be too dark nor too bright. The lines of the Bahtinov interference pattern have to be clearly visible.
- The chosen star shouldn´t be positioned in the center of your live view, because most telescopes or lenses, although corrected, do not produce a plane field of view. We recommend to position the star in the outer third of your image. That way, you will achieve a better overall sharpness across your field of view.
Turn on your camera and watch your selected star on the live view screen.
If the image isn't yet in focus, the central line of the Bahtinov
pattern is shifted. Adjust your focuser until this very line sits
exactly between the other two lines.
Now you have achieved optimal focus. Remove the mask from your optics and you can start the exposure of your object.
- Correctors and Barlow lenses are not a problem
3 screws covered in rubbery plastic for attachment
Permits very precise focusing. You can easily identify the optimal focus position