Since we are considering changing our DARM offset (Sheila has some nice plots forthcoming), I have measured the LSC FF transfer functions that we are going to need. 

I used a 13.72 X0 fringe offset to give 40mA sum on DCPDs. (Previous tests done in the last week were with 41mA of DCPD sum, but 40mA seemed like a nice round number, 2x our current 20mA sum).  I measured SRCL, MICH, and PRCL to DARM, with their current FF filters engaged and operating, so these will be iterative filters. The PRCL iterative excitation, and the FF_to_DARM excitation had to be reduced in amplitude by a factor of 2 so that I didn't saturate the DCPDs. The PRCL iterative could have been reduced a bit more.

I'll fit these iterative transfer function measurements, so that they are ready to implement when we decide to change the DARM offset.