Between the 3rd and 4th mosaic panel of a six panel mosaic, PHD2 failed calibration. Somehow the log shows that PHD2 loaded the wrong profile or was reset. The exposure also changed from 2.5s to 1.0s.
Guide log excerpt:
HD2 version 2.5.0, Log version 2.5. Log enabled at 2015-07-17 23:41:58
Calibration Begins at 2015-07-17 23:43:23
Equipment Profile = My Equipment
Camera = SBIG ST-i Color CCD Camera
Exposure = 1000 ms
Pixel scale = unspecified, Focal length = unspecified
Mount = Gemini Telescope .NET, Calibration Step = 750 ms, Assume orthogonal axes = no
Dec = 44.6 deg, Hour angle = -2.84 hr, Pier side = West, Rotator pos = N/A
Lock position = 31.996, 117.165, Star position = 32.013, 117.031
Direction,Step,dx,dy,x,y,Dist
West,0,0.000,0.000,32.001,117.051,0.000
West,1,0.051,0.051,31.950,117.000,0.072
West,2,0.085,0.056,31.917,116.995,0.101
West,3,0.019,0.370,31.983,116.681,0.370
West,4,-0.065,0.494,32.066,116.557,0.499
West,5,0.420,0.986,31.582,116.065,1.072
INFO: Guiding parameter change, Exposure = 2500 ms
Calibration Begins at 2015-07-17 23:44:25
Equipment Profile = My Equipment
Camera = SBIG ST-i Color CCD Camera
Exposure = 2500 ms
Pixel scale = unspecified, Focal length = unspecified
Mount = Gemini Telescope .NET, Calibration Step = 750 ms, Assume orthogonal axes = no
Dec = 44.6 deg, Hour angle = -2.82 hr, Pier side = West, Rotator pos = N/A
Lock position = 31.919, 116.215, Star position = 31.894, 116.159
Direction,Step,dx,dy,x,y,Dist
West,0,0.000,0.000,31.948,116.206,0.000
West,1,0.232,0.259,31.716,115.947,0.348
West,2,0.244,0.479,31.704,115.726,0.538
West,3,0.255,0.814,31.693,115.392,0.853
West,4,0.294,0.952,31.655,115.254,0.997
West,5,0.234,1.103,31.714,115.103,1.128