nou replied to the topic 'Linear 1 Pass focussing problem' in the forum. 2 months ago

I think you need to decrease step size. Set it to that value that 2-3 step from ideal focus it will give you HFR around 5. Another good estimate is set step size to CFZ which is calculated as 4.88*550nm*(f-ratio^2) for f/4 scope it is 42944nm or 43um. Then you just need to calculate how much does one step of focuser move.

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