Interference fringe Printer test

Ever wanted to see printer step or micro step errors then this is the test for you.

Honestly this test has way more resolution than a printer can handle. In a perfect world the test would be used to calibrate out position errors and improve printer accuracy.

:added May 2020 stl file to print in vase mode, no corners so you can print it fast. I converted my Cetus electronics to Duet2 WIFI electronics
https://forum.duet3d.com/topic/7709/controlling-a-cetus3d-with-duet3d-0-8-5
new pic is the Duet2 printing the new stl file. Layers are 0.15mm thick which is the vertical bands spacing for calibrating horizontal measurements.

My tuned up cetus mk2 with IKO linear rails printed the walls in the picture. Each wall is 0.3 mm thick. The edge of each layer forms a cylinder which also doubles as a lens. When the two lens interact your mind sees a pattern. The interference band down the middle has the smallest horizontal errors because the horizontal stepper position is almost identica