Keep stray light from your focuser with this one piece Kydex Light Shield. Ends Velcro together forming a fitted cylinder which secures inside your tube with Velcro tabs between the spider vanes. Slots fit securely over the ends of your secondary spider vanes inside your telescope tube,
Individually designed to fit your tube diameter and three or four vane spider. Slots and perimeter corners are rounded for safety. Kydex is waterproof, rigid and rugged. Light shield orders are manufactured every three weeks.
Calculate the Light Shield size using the three measurements shown in the photos above and example below. Tape a ruler to your tube opposite the focuser with most of the ruler extending beyond the top of the tube. This example for a 12 inch inside diameter telescope tube will help you calculate the square inches for placing an order:
DimensionDirectionsResultAThis is the amount of baffle inside the tube.
If the spider vanes are 3" from the top your tube.
Add 1.5" for slotted section below spider vanes:
3" + 1.5" = 4.5"
4.5"BThis is the amount of baffle you want extending above the tube.
In the above example you can see 7" visible above tube edge.
Add 1". Add more if you prefer:
4.5" (A) + 7" (B) = 11.5"11.5"C
This example assumes a 12" inside diameter tube.
Multiply 12" the tube diameter by pi (3.1415)
12" x 3.1415 = 37.7"
Add 2" for the Velcro overlap to secure the ends:
37.7" + 2" = 39.7"
39.7"Sq. InchesTo get the square inches of your baffle:
Multiply the sum of (A) and (B) 11.5" with (D) 39.7" = 434 sq"434 sq"
Filed under: Eyepieces & Accessories