Quote Originally Posted by White-Light View Post
You do need an oscilloscope to check the minimum scanner speed on all the patterns as there is a minimum scanner velocity required to use the simple method. If in any pattern the scanner drops below the minimum velocity you're screwed so far as using the simple method is concerned.

One conclusion in the Calculating Scanning parameters article of Patrick Murphy and Greg Makhov, is :

The result of this analysis is that by scanning the beam, the allowable MPE is increased only by a relatively small factor relative to the average power MPE. Makhov states “Since the increase in MPE as a function of scanning is small (only 4 to 10 times), scanning parameters are a minor factor. To stay within the MPE, the accessible irradiance is the major factor.”
Show measurement is vastly simplified. The show operator only needs to measure the accessible exposure at the point of closest audience access. If the operator sets the power to about 10 mW/cm2 (four times the 2.5 mW/cm2 average power MPE), this will approximate the single-pulse MPE limit for the audience-scanning portion of the show.
This simplification assumes the show has been designed so effects are kept moving, and the scanned shapes are smooth with no “hot spots”.

So if you want to use the simplified method, after having determined the static laser beam parameters, you have to ensure you have only patterns and effects which presents a minimum velocity, and no hot spots.

This can be done by using a scanfail card which blank the beam immediately if a min velocity is not reached, or if dwell time (time the beam remains at the same place) is exceeded.
But you have to be sure the scanfail card is adjusted to respect the min velocity at the point of closest audience access... And this can require an oscilloscope