Summary of grid tests I put some important information in brackets: {ZA,parallactic angle} Unless otherwise stated, wires were vertical A Jan 8; Jupiter, hwp=20 {40,-30} 27943-6 LAST FILE IS FIRST ANGLE B Jan 9; Saturn hwp=20, {near transit} 28069-72 C Jan 10; Jupiter, hwp=30 {35, -10} 28473-6 D Jan 10; Jupiter, hwp=20 {35, -10} 28477-80 E Jan 11; Mars, hwp=35 {15, -80} 28482-5 F Jan 11; Mars, hwp=35, wires rotated 45 deg CW {15, -80} 28486-9 G Jan 12; Saturn, hwp=35, wires rotated 45 deg CW {10, -80} 28907-10 H Jan 12; Saturn, hwp=125, wires rotated 45 deg CW {10, -80} 28911-14 J Jan 13; Saturn, hwp=35, {near transit} 29170-73 K Jan 15; Jupiter, hwp=35, {40, -40} 29876-79 Analysis: From doing eyeball estimates of the position of the peak in H-V, and (empirically) adding 22.5 degrees to the ones with wires rotated by 45 degrees CW, I get the following numbers for the peak in H-V: 50, 55, 45, 55, 50, 57.5, 47.5, 47.5, 50, 50 mean: 51 std. dev: 4 The mean of the first five values is 51 also, so there is no evidence of any long term drift.