In this figure we consider three level of reconstruction error of 0.5, 1.0, and 2.0 respectively. If we examine the case of 1.0 residual. However, if the AO system can not achieve an overall phase error lower that the magnitude gain is strongly reduced or even nulled. This is shown considering that using a tilt modulation of permits a 2 mag gain when the overall system phase error is lower than 2 rad 2 and decreases smoothly after this limit. Finally when using a modulation of about the gain is reduced to about 1.5 mag but this gain is retained until is lower than 5 rad 2 .
Similar results hold for the other values of considered.
This demonstrates the better behavior of PS with respect to SHS in terms of limiting magnitude even in partial correction AO systems.