Bahtinov Focus Mask  and Fine Focuser for all Celestron 6" SCT Telescopes

Description

Fine tuning the focus on a standard Celestron 6" SCT can be quite difficult. The Bahtinov mask slips directly onto the front of the scope and allows you to ensure your telescope is in perfect focus. When you're doing using the telescope, you can simply place the mask back on the telescope and place the cover over it. The fine focuser slips onto the standard focus knob and allows you to make fine adjustments. It increases the width of the focus knob by over 100%. The original focus knob is still accessible, if you need to make large focus adjustments.
Both items are made from high quality flexible plastic and can take the abuse of constant use, dropping and anything else that may happen to them. They're orange in color which makes it easier to find a night.
How To Use
Using a Bahtinov mask is really quite simple. Using your telescope, look at a bright star in the sky and try to focus the telescope as much as possible. Now, place the mask on the end of the telescope. Use the highest eyepiece you have (if you're using a camera, zoom in as much as possible using the viewfinder). You should see 3 multi-colored lines, two of them that form an X and 1 close to the middle. Using your fine tune focuser, adjust the focus slightly until the middle line is in the middle of the X. Now remove the mask and you're perfectly in focus.