BuckeyeStargazer Duncan Mask for SCT Collimation - For Celestron Telescopes
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Important note: Duncan masks are a collimation aid. These can be used in conjunction with collimation knobs sold by Bob's Knobs and others. Duncan masks can also be used for rough focusing but they are not effective tools for critical focus work. For that, you may want to look at Bahtinov or TriBahtinov masks instead.
A Duncan Mask can be used to easily and quickly collimate the secondary mirror of your SCT. Instructions are provided below.
BuckeyeStargazer's Duncan collimations masks comes in sections that "snap-fit" together and can be taken apart for easier storage. They are available for many different Celestron SCT telescopes as listed below.
Model:
- C5 (Hole dia. 50mm): For Celestron 5" SCTs
- C8 (Hole dia. 71mm/78mm): For Celestron 8" SCTs
- C8-NonFastar (Hole dia. 67mm): For Celestron 8" SCTs (non-Fastar pre-1998)
- CClassic8 (Hole dia. 72mm): For Celestron "Classic8" (specific scope only)
- C9.25 (Hole dia. 91.5mm/106mm): For Celestron 9.25" SCTs
- C9.25-NonFastar (Hole dia. 85mm): For Celestron 9.25" SCTs (non-Fastar pre-1998)
- C11-NonFastar (Hole dia. 92mm): For Celestron 11" SCT (non-Fastar/Hyperstar)
- C11 (Hole dia. 98mm/111mm): For Celestron 11" SCTs
- C8 (Hole dia. 71mm/78mm): For Celestron 8" SCT
- C14 (Hole dia. 116mm/127mm): Celestron 14" SCTs
- C14-NonFastar (Hole dia. 104mm): For Celestron 14" SCT (non-Fastar pre-1998)
Additional Notes:
- C5 is one piece, 14" and larger are 6 sections, all others are 3 sections.
- Hyperstar Note: The C6, C8, C9.25, C11 and C14 Duncan Masks accommodate both Hyperstar and native Fastar/secondary mirror configurations. The central hole is sized for the Hyperstar and the mask includes a snap fit bushing to decrease the diameter for the Fastar ring.
- For Hyperstar versions, the center hole accommodates the Hyperstar, and will not go around cameras that are wider than the Hyperstar body. In such cases the camera must be removed for installation and removal of the mask.
If you are unsure about which mask you need:
- Measure the inside diameter of the tube at the corrector and ensure that it is slightly larger than the Mask OD listed below, and
- Measure the outside diameter of the secondary housing and ensure that it is slightly smaller than the Mask ID listed below.
Please note that this is a 3d printed plastic part.
- BuckeyeStargazer's items are made of PETG plastic and can handle temperatures of up to 80°C (175°F).
Other Information
- Country of Manufacture: United States
Important note: Duncan masks are a collimation aid. These can be used in conjunction with collimation knobs sold by Bob's Knobs and others. Duncan masks can also be used for rough focusing but they are not effective tools for critical focus work. For that, you may want to look at Bahtinov or TriBahtinov masks instead.
A Duncan Mask can be used to easily and quickly collimate the secondary mirror of your SCT. Instructions are provided below.
BuckeyeStargazer's Duncan collimations masks comes in sections that "snap-fit" together and can be taken apart for easier storage. They are available for many different Celestron SCT telescopes as listed below.
Model:
- C5 (Hole dia. 50mm): For Celestron 5" SCTs
- C8 (Hole dia. 71mm/78mm): For Celestron 8" SCTs
- C8-NonFastar (Hole dia. 67mm): For Celestron 8" SCTs (non-Fastar pre-1998)
- CClassic8 (Hole dia. 72mm): For Celestron "Classic8" (specific scope only)
- C9.25 (Hole dia. 91.5mm/106mm): For Celestron 9.25" SCTs
- C9.25-NonFastar (Hole dia. 85mm): For Celestron 9.25" SCTs (non-Fastar pre-1998)
- C11-NonFastar (Hole dia. 92mm): For Celestron 11" SCT (non-Fastar/Hyperstar)
- C11 (Hole dia. 98mm/111mm): For Celestron 11" SCTs
- C8 (Hole dia. 71mm/78mm): For Celestron 8" SCT
- C14 (Hole dia. 116mm/127mm): Celestron 14" SCTs
- C14-NonFastar (Hole dia. 104mm): For Celestron 14" SCT (non-Fastar pre-1998)
Additional Notes:
- C5 is one piece, 14" and larger are 6 sections, all others are 3 sections.
- Hyperstar Note: The C6, C8, C9.25, C11 and C14 Duncan Masks accommodate both Hyperstar and native Fastar/secondary mirror configurations. The central hole is sized for the Hyperstar and the mask includes a snap fit bushing to decrease the diameter for the Fastar ring.
- For Hyperstar versions, the center hole accommodates the Hyperstar, and will not go around cameras that are wider than the Hyperstar body. In such cases the camera must be removed for installation and removal of the mask.
If you are unsure about which mask you need:
- Measure the inside diameter of the tube at the corrector and ensure that it is slightly larger than the Mask OD listed below, and
- Measure the outside diameter of the secondary housing and ensure that it is slightly smaller than the Mask ID listed below.
Please note that this is a 3d printed plastic part.
- BuckeyeStargazer's items are made of PETG plastic and can handle temperatures of up to 80°C (175°F).
Important note: Duncan masks are a collimation aid. These can be used in conjunction with collimation knobs sold by Bob's Knobs and others. Duncan masks can also be used for rough focusing but they are not effective tools for critical focus work. For that, you may want to look at Bahtinov or TriBahtinov masks instead.
A Duncan Mask can be used to easily and quickly collimate the secondary mirror of your SCT. Instructions are provided below.
BuckeyeStargazer's Duncan collimations masks comes in sections that "snap-fit" together and can be taken apart for easier storage. They are available for many different Celestron SCT telescopes as listed below.
Model:
- C5 (Hole dia. 50mm): For Celestron 5" SCTs
- C8 (Hole dia. 71mm/78mm): For Celestron 8" SCTs
- C8-NonFastar (Hole dia. 67mm): For Celestron 8" SCTs (non-Fastar pre-1998)
- CClassic8 (Hole dia. 72mm): For Celestron "Classic8" (specific scope only)
- C9.25 (Hole dia. 91.5mm/106mm): For Celestron 9.25" SCTs
- C9.25-NonFastar (Hole dia. 85mm): For Celestron 9.25" SCTs (non-Fastar pre-1998)
- C11-NonFastar (Hole dia. 92mm): For Celestron 11" SCT (non-Fastar/Hyperstar)
- C11 (Hole dia. 98mm/111mm): For Celestron 11" SCTs
- C8 (Hole dia. 71mm/78mm): For Celestron 8" SCT
- C14 (Hole dia. 116mm/127mm): Celestron 14" SCTs
- C14-NonFastar (Hole dia. 104mm): For Celestron 14" SCT (non-Fastar pre-1998)
Additional Notes:
- C5 is one piece, 14" and larger are 6 sections, all others are 3 sections.
- Hyperstar Note: The C6, C8, C9.25, C11 and C14 Duncan Masks accommodate both Hyperstar and native Fastar/secondary mirror configurations. The central hole is sized for the Hyperstar and the mask includes a snap fit bushing to decrease the diameter for the Fastar ring.
- For Hyperstar versions, the center hole accommodates the Hyperstar, and will not go around cameras that are wider than the Hyperstar body. In such cases the camera must be removed for installation and removal of the mask.
If you are unsure about which mask you need:
- Measure the inside diameter of the tube at the corrector and ensure that it is slightly larger than the Mask OD listed below, and
- Measure the outside diameter of the secondary housing and ensure that it is slightly smaller than the Mask ID listed below.
Please note that this is a 3d printed plastic part.
- BuckeyeStargazer's items are made of PETG plastic and can handle temperatures of up to 80°C (175°F).
Other Information
- Country of Manufacture: United States
BuckeyeStargazer Duncan Mask for SCT Collimation - For Celestron Telescopes