Celestron C8 StarSpike Mask

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This is a clip-on mask for a Celestron C8 telescope. It creates nice star spikes for astrophotography as if the secondary mirror would be held with arms like in a newton or RC telescope (or Hubble Space Telescope ;)). It is not made for visual observations. It is designed for my C8 from 1992 (black tube, no hyperstar option on secondary mirror). If you take photos from one object over several nights/sessions, it is important that the arms of the mask are always rotated exactly the same way. Otherwise you'll get multiple slightly rotated star spikes which might look artificial. To prevent the mask from beeing slightly rotated every time you put it on, I designed 4 little clamps that hold each arm at always the same position/rotation. You have to glue these 4 clamps on the plastic ring that holds the Schmidt plate with double sided sticky tape. The best way to do this is to put tape on the clamps, then put them on the arms of the mask an then clip the mask with the claps still on the arms of the mask on the secondary mirror with the 3 holes exactly over the collimation screws. Then slightly press on the clips to give them a good fit. Beware of touching the Schmidt plate. Don't apply too much pressure on the middle cap of mask when it's on the secondary mirror! Thereafter you can remove or put on the mask always in the same orientation. The clips are small enough that you can still cover the C8 even with the clips installed. The cap of the mask is designed like the original secondary mirror housing and has different functions: - You can still reach the three collimation screws through the holes. - You can clip on the original orange cap for the secondary mirror. - You can put on a bahtinov mask on top. - You can stack multiple star spike masks to get multiple star spikes in the rotation you like.