
Instead of parallactic angle, try a synthetic tilt
based on the phase angle.

Evening crescent tilts left
Morning crescent tilts right

MaxTiltAng = ±45 degrees

when at Full Moon = Min TiltAng = 0
When at New Moon  = Max TiltAng = 45


TiltAng = MaxTiltAng * sin(PhaseAng)


For
PhaseAng = 90
TiltAng = 45 * sin(90) = 45 * 1 = 45

For
PhaseAng = 270
TiltAng = 45 * sin(270) = 45 * -1 = -45


For
PhaseAng = 0
TiltAng = 45 * sin(0) = 45 *  = 0



For
PhaseAng = 180
TiltAng = 45 * sin(180) = 45 * 0 = 0












---------------------------------------------------
$TiltAngDeg = (45 * sin(deg2rad($PhaseDeg))).'deg';

---------------------------------------------------
Inline code to tilt the IMG:

style="-o-transform:rotate($TiltAngDeg);-ms-transform:rotate($TiltAngDeg);transform:rotate($TiltAngDeg);"











