As you want it - AstroGoods mounts perform.
 
Mirror Masks: Visual and Imaging

Visual masks
 

12" and 6" masks shown.

Current design example 10" mask

Turned Down Edge Correction
What is TDE?


For standard sizes:
153mm, 200mm, 250mm, 304mm, 6",8", 10", 12" and 12.5" mirrors.
.
Custom size:
enter your custom size masks entering the outside diameter (O.D.) and inside diameter (I.D.) required (up to 12.5" diameter and 1.5" wide) in the measurements box.

Our TDE masks cover 1/8" of the mirror surface perimeter.
Construction: Lightweight 1/8" thick acrylic, black matte on one sidewith three 0.25" holes spaced at 120 degrees allow you to precisely center the mask on the mirror's edge. Use double sided sticky tape or small Velcro adhesive dots to attach on top of mirror clips.

Size
Choices
Price
Standard
$20
Custom
$25

 
Shipping information
 
Your name.
E-mail address.
Repeat e-mail address.
Country.
Zip or postal code.




About turned down edge (TDE):

See #2 How to improve image quality on masking mirrors .

"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." - Mel Bartels

Imaging masks
 

Remove mirror clip diffraction spikes

Masking the clips on your primary will improve star images by eliminating flare. The images at left show a primary mirror without and with our mask. The star images below show results without and with the mask.

Precision cut from light weight 1/8" thick acrylic, one side flat black. Adhere with small Velcro dots or similar.

Mask centers perfectly: aligns precisely with outside edge of mirror clips.

Prices are for up to 12.5" mirrors. Inquire for larger sizes.
 
 

Order
$25 each. Inquire for larger sizes.
Mirror diameter in mm.
Clip overhang of mirror.
Clip width.

 
Shipping information
 
Your name.
E-mail address.
Repeat e-mail address.
Country.
Zip or postal code.



Click images to englarge.