Primary Mirror Edge Masks: Image Sharpening for 6", 8", 10", 12", 12.5" mirrors.

Description

We ship mirror masks orders (received by Thursday 5 PM Pacific) weekly on Friday by US Post Office. Delivery transit time is 5 days for domestic delivery.  Please state your mirror size when placing an order.  Pricing includes shipping within the U.S.
Mirror masks can help sharpen your telescope's images, showing finer detail in lunar, planetary and double stars. Masks correct Turned Down Edge (TDE) and may hiding this common image softening edge defect.
This is from Mel Bartels on the topic: "Turned down edge (TDE) Outside of proper parabolization, edge problems are the most common maladies afflicting mirrors. A turned down edge, or TDE, is a narrow zone, no more than 1/8 inch [3mm], at the extreme edge that turns downward, focusing long. If the zone is wider then it is called a rolled edge. Rarely the extreme edge will turn upward, focusing short. This is called a turned up edge."
Constructed from 0.125" thick matte black acrylic, masks are stiff and light weight.
Each mask has long slots to the mirror edge allowing precise centering. Small notches provide a mark for placing mask on top of mirror clips. Use Velcro dots or squares you provide to secure on mirror clips.
Specify mirror size when ordering:
Mirror Size
Mask Inside Diameter
Mask Outside Diameter
6.0"
5.75"
7.0"
8.0"
7.75"
9.0"
10.0"
9.75"
11.0"
12.0"
11.75"
13.0"
12.5"
12.25"
13.5"