Flexures Map

Next figures show the shifts of the position of lines in comparison lamp frames due to flexures of the telescope and instrument.
As can be seen, at the red arm the maximun shift is 0.12 pixels (1.8 µ) and 0.64 pixels at the blue arm (9.6 µ).
Frames were taken with the telescope at zenital distances from 60 degrees to the East to 60 degrees to the West, with 15 degrees steps (red arrows). Later, telescope has been moved from Z = 45 degrees South to Z = 45 North (green arrows). These two sequences were done with the slit oriented E-W and repeated with the slit S-N (blue and pink arrows).
Left arrows means that the lines positions are measured at the left extreme of the frame and right arrows at right extreme.



Site#22b (Blue)




Site#20b (Red)




Santos Pedraz Marcos
Last modified: Jan 20 2001