The attenuated output from the front end, or seed, laser was admitted into the high power oscillator ring. No signs of clipping on the intermediate optics was observed. However the overlap between the beam promptly reflected from the oscillator's output coupler and the beam that traversed the ring was slightly off - the interference fringes were clearly left of centre. This was corrected for. The mis-alignment of the output coupler was most likely caused by the drag wipe cleaning the previous day. Each laser head was powered up with 5A of pump current. No bright spots were observed on the optics that would indicate some kind of point damage. Each head was powered up to 50A and again, no point damage spots were observed. The oscillator was then fully powered up, starting at 40A-45A per head. The laser power was noticeably down. The beam from the oscillator, shown in FirstTurnOn1.png, was ugly but stable. My interpretation of this was that there was no point damage on the optics but that the resonator was severely mis-aligned. The exact reason for why the resonator would have become mis-aligned is not clear to me. Adjusting the output coupler did improve the beam shape but not the output power. A more thorough alignment process will be embarked on tomorrow.