ATM Buddytools for Amateur Telescope Makers

Spherometer feet radius

r = (a × b × c) / (4 × Area) — a, b, c = distances between ball centers

Create spherometers in the Hardware tab to quickly load their dimensions here.

Radius of feet: 80.0000 mm

Deviation for a 0.001 mm measurement error: ± 0.0006 mm

Measure to 0.001 mm, ball diameter included: that precision is what drives the resulting radius.

Measurement A, outside to outside (mm):

Measurement B, outside to outside (mm):

Measurement C, outside to outside (mm):

Ball diameter (mm):

Measure from the outer edge of one ball to the outer edge of the next: one ball diameter is subtracted to get the center-to-center distance.

This radius can be saved as a spherometer's feet radius in the Hardware tab.

A project by Lucas Sifoni, Paul Faÿs from Gallifrey Optics, and Raphaël Labro from La3emedim.fr
Contribute on github.

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