Nắp diffuser push-fit cho kính thiên văn để tạo flat bằng áo thun

A parametric (OpenSCAD) generator that will generate a pair of press fit rings to make a diffuser from a white t-shirt to use as a flat field generator. This is an alternative to my twist lock diffuser ring.

This is sized to fit the Celestron Origin, but you can create one to fit different scopes by using the openscad file.

1. Place the inner ring on a flat surface with the bevelled edge downwards (the bevelled edge helps with locating when you fit to the dew shield)

2. lay the t-shirt over the ring

3. Press fit the outer ring over the t-shirt and lower ring. Make sure the shoulder of the ring is uppermost

4. Pull the t-shirt tight

This fit a double layer for me, but the t-shirt was thin.

Reduce tolerances to use it with a cutout made from tracing paper or draughting film (produces an even, neutral field). Use the inner ring to trace out a circle, cut it out and lay it on the shoulder of the outer ring. Sandwich it in with the inner ring.

I also have a twist-lock version better suited for tracing paper at 

and a filter tray for the Celestron origin at