Differences

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--- calibration [2025/10/10 22:12] – holtz
+++ calibration [2025/10/13 01:37] (current) – jasonj
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 ===Position===
-The calibration spot moves up and down as the calstage is moved. To move the calibration stage left/right one needs to adjust one of the screws on the mirror mount for the mirror in front of the Shelyak. I believe that turning the top screw CW (from behind the mirror) moves the spot to the right.
+The calibration spot moves up and down as the calibration stage is moved. To move the calibration stage left/right one needs to adjust one of the screws on the mirror mount for the mirror in front of the Shelyak. I believe that turning the top screw CW (from behind the mirror) moves the spot to the right.
 To position the calibration spot with the iodine cell, the cell can be tilted by adjusting the three screw on the front ring. Need to take care not to overtighten and potentially break the cell, so adjustments should be made by both loosening some screws and tightening others! Moving the cell with the bottom two screws (one in, one out) should move spot left/right, moving the cell with compensating motions of top screw and the bottom two together should move spot up/down.
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 {{:test:pixflat_flat.png?direct&400}}
-The detector is remarkably flat, with typical variations well under a percent, so even skipping flat fielding wouldn't introduce a large amount of fixed "noise". Upon higher inspection, there is a low level pattern seen here:
+The plots on the right show horizontal and vertical cross-sections through the middle of the chip. The detector is remarkably flat, with typical variations well under a percent, so even skipping flat fielding wouldn't introduce a large amount of fixed "noise". Upon higher inspection, there is a low level pattern seen here:
 {{:test:pixflat_flat_zoom.png?direct&400}}
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 ====Wavelength calibration====
+====Stability====
+Sequences of calibration frames:
+- UT2510xx : flats and ThAr through fiber 2 (science) every half hour for 12+ hours
+- UT251011 : flats and ThAr through both fiber 1 (direct) and fiber 2 (science) every half hour for 12+ hours