How BackfocusLab calculates your result
A reproducible dimensional check with transparent formulas and no hidden compatibility score.
Enter an actual rig, not just a camera model
Replace every example value with a manufacturer specification or your own measured value. Arrange the components in physical order from the specified rear reference plane to the sensor. Use the arrows to reorder components; dragging is not required.
Four checks, separate conclusions
The workspace checks spacing, nominal metric-thread handoffs, sensor diagonal against the image circle, and whether the train terminates at a sensor. A pass in one category cannot cancel a warning in another. The telescope-side interface, engagement depth, and optical performance are outside this model.
Take the evidence with you
Export a JSON plan to preserve the complete input set, or a result JSON for an agent-readable handoff with units and unresolved checks. Share rig creates a URL fragment containing the full train after an explicit disclosure. It does not upload your plan to an application server. Anyone with the link can read it.