Fisher transform
Price position in its range, reshaped so turning points stand out as sharp peaks.
Formula
x = the bar midpoint's place in its N-bar range, mapped to ±1 and smoothed Fisher = ½ × ln((1 + x) ÷ (1 − x))
How to read it
Extremes beyond ±1.5 mark stretched moves; the line crossing its trigger (itself one bar earlier) marks a turn.
How to use it
Sharp turning-point signals in markets that oscillate.
In Kereon
Charts · Superchart. Default 9; lines at −1.5, 0 and +1.5. Ehlers' recursion, clamped at ±0.999 as his code clamps it.
Also called: fisher, ehlers.