====== HP ======
=== Grating Synchronization === 

HP is a routine that moves the bottom micrometer to optimize the intensity going to the Photomultiplier tube at the operating position of the top micrometer. This routine is only used on MKIII (Double spectrometer) instruments.\\

In double spectrometer instruments, it is important that the two micrometers remain synchronized such that they are both set to the same wavelength. The HP test, tests for this condition and makes an adjustment, if necessary.\\ 
For this test the Standard lamp is used as a light source. The Standard Lamp is turned on, the prism is pointed to lamps, the Iris is opened, FW#1 is set to Position 1, and FW#2 is set to position 0. Micrometer #2 is then moved relative to Micrometer #1, and is adjusted such that maximum intensity will occur - an adjustment of more than 10 steps results in the test being repeated. 


Typically this routine is combined with [[fr|FR]] and [[hg|HG]]