AF completion even when the AF routine doesn't finish the parabolic or hyperbolic curves

[koichi fun]

With some short-travel focusers, FSQ106ED with F3 reducer in may case, the focus point is very near to the zero. The AF routine stacks when it tries to go beyond the zero, while it passes through the minimum HFR. It would be nice, if the focuser stopped after it reaches the zero then evaluate the focus point with the data taken so far.

[Stefan B]

Removing version: 2.0 Beta (automated comment)

[Stefan B]

A focuser needs enough travel to properly determine the focus point. If there is not enough travel the autofocus routine should also fail in the latest versions.

having only a partial curve will not give a precise focus measurement.

[koichi fun]

I agree with you on the point that a partial curve will not give a correct focus point. However, one of my equipment has its focus point near the zero position. A smaller step does not work well to find it, while a modest step cannot complete the parabolic curve. Since even such an incomplete curve has a definite minimum of HFR, I set the focus position manually. I hope AF routine admits, for example, 60% of fitting curve with a definite minimum, near the zero point.

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