AstroZap Focusing Cap 152mm
This focus cap is a multipurpose tool with a quick "shutter" like action that you will be glad to add to your collection. When you want to focus the image during sessions, turn the center knob to "open" to reveal a trio of off-axis masks, allowing the focusing cap to operate the same as a simple Bahtinov mask. Rotate the wheel once again to place the cap in the "closed" position. You can either take dark frames or use it as you would any dust cap.
This Astrozap Focusing Cap is made from lightweight aluminum and powder-coated black; it is an excellent example of proud and great workmanship.
For installation: three thumbscrews hold the Focusing Cap firmly in place; no tools or plastic plugs are needed.
The AstroZap Focusing Cap 152mm will fit 193mm-204mm optical tubes.