Probably a noob question, but I&#39;m not sure of the difference between these two parameters. I see from the documentation that one is &quot;phase-matched&quot; and the other is not, but after messing around a bit I&#39;ve been unable to come up with a scenario in which behaviour differs when using one or the other. Can anyone shed some light on the difference?<br>
<br>Cheers,<br>Sean<br>