How important is pulse width during laser treatment?

Your frustration with the laser treatment may have less to do with the laser settings and more to do with the fact that so many, relatively expensive, faddish, "bells and whistles," energy-based devices lack the hard science to truly support their use and are, in fact, far more backed up by heavy duty marketing hype. You would be wise to consult a board certified dermatologist with experience and expertise in appropriately treating rosacea so that you can begin a proper treatment regimen for both the outbreaks and the flushing and redness. Hope this helps. Best of luck.

Joules is the amount of energy, and pulse duration is how long it takes to create a pulse. a short pulse is similar to "searing a steak" versus a long pulse is similar to "baking a steak". Therefore, to make a treatment more intense, one would increase the joules and decrease the pulse width. So, 4J and 12ms is LESS intense than 9 J and 5ms.