edit: I doubt its 593.5. it could be, but creating that off a yittrium garnet (YAG) is quite difficult...usually they use an orthovanadate (YVO4) or yttrium Perovskite (YAP) to generate 1340/1342nm. That line is pretty weak in the YAG crystal structure, but it depends entirely on how the mirror coatings have turned out if they were fluked and drifted one way or the other due to the way they were produced its not impossible for it to be switching to 593 while cold and the 1342 line is stronger, then as it warms it favors the 1319 line. I tend to find the 589s tend to be hit and miss on the optics, as there are so many lines packed into that tiny area of the spectrum that can be created. one of my 593s has such overly high gain it also still weakly lases (leaks) light in the red and green with it in super tiny amounts.