Newton Adjustment and Cleaning by Disassembling the Mirror Cell:

Newtonian Adjustment and Cleaning by Disassembling the Mirror Cell:

To adjust the secondary mirror, a sheet of paper is often placed between the secondary mirror and the primary mirror to better and more clearly assess the position of the secondary mirror. However, it's quite cumbersome to simply place the paper behind or in front of the secondary mirror. This makes it easier to remove the primary mirror and the mirror cell. We built a device for this adjustment work that allows you to clamp a piece of black cardboard to a rod in front of the secondary mirror.

Or if you want to clean the primary mirror of dust.

In most Newtonian telescopes, the primary mirror cell is easy to remove. This usually requires removing four screws that don't have a locknut, making it easy to reinstall. It's important that the mirror sags downward under its own weight when removed, potentially causing it to touch the tube.

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