First Ronchi Test after Two Hours Polishing

2 Hours polishing with CEO2.

150 LPI Ronchi Grating and green LED source.

Inside ROC	Outside ROC
The curving lines indicate an oblate ellipsoid rather than the desired sphere. The deviation is slight however, and at this early stage of polishing, not terribly relevant. What is good is that the surface is smooth and there are no obvious problems.