Reflector adjustments jan01 (M_TD1)

• Figure 1: The surface errors measured in dec00 before any adjustments were made.  The arrow length is proportional to the error. 1 tick mark is 3 mm. The angle is also proportional to the error. +/- 180 is +/-  10 mm. Errors larger than 10 mm are clipped to 10 mm and +/- 180 degrees.  The statistics in the table include all points except for 48 points with error > 30 mm.
• Figure 2: The surface errors measured in jan01 after the first round of adjustments.  The arrow lengths, angle, and clipping are the same as Figure 1.  The statistics in the table include all points except for 10 points with error > 30 mm.
• Figure 3: Shows the reflector errors after the first adjustment. The arrow length is proportional to the error (but the scale is changed so 1 tick mark is 2 mm). The angle of the arrow shows the fractional change in error:

(errorBefore-errorAfter)/errorBefore - 1.
• 0 degrees is perfect.
• 60 degrees is too far by 1 times,
• 120 degrees is too far by 2 times
• - 60 degrees is no motion
• -120 degrees is the wrong way by 1
• -180 is the wrong way by 2 times.
Errors < 1 mm have been set to 0. Errors > 30 mm have been clipped to 30 mm. Anything black was turned too far. Anything red was not turned far enough. You can see the large errors in the center (green, blue) that point at -60 degrees. These are on the new panels that have no adjusters beneath them so their error did not change. The large errors at -120 degrees were turned the wrong direction.
• Figure 4: The rms. error, mean error, minimum error, and maximum error are computed for each main cable (running north/south). These values are plotted versus the east/west distance from the center of the dish (the cables are spaced every 25 feet). The large spikes in the center cables are coming from new panels covering the opening in the center (see figure 5). The average shows a slight curvature toward the edges. All the data points were included.
• Figure 5: This shows the bad points on the new panels that cover the hole in the center. The 7 strips are the 7 east/west rows closest to the center (limited to +/- 300 feet from the center). The average position of a strip is its east/west distance in feet from the center of the bowl. The offset from the average position is the error in mm. The largest error is on the blue strip that goes through the center of the dish. It has an error of about 145 mm.

processing: x101/dish/M_TD1/doitjan01.pro for a description

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