The data used for this analysis is from C:/data/CD016/cd016_2013oct/53. The frames were taken with the following configuration with a total of 20 repeat frames: 25 1 egos (N2 S0 N3 S0 N3 S0 N1 D0); Slit 3; BP14100; Echelle angle = 37; Cal BB source at 22 C. For the images with light (file numbers 1958-1977) the 14 pixel decker was used so that the orders did not overlap and for the dark images (file numbers 1978-1997) the lens mirror was used.
To examine possible light leaks, the dark regions between the order were identified and then the corresponding pixels on the dark frames were used to subtract off any background. The first read was taken as a baseline and all other reads were subtracted from the first read. Below shows the results from the analysis. Comments and questions are always appreciated.
- Panel A. shows the results from the light frames minus the dark frames. The lighter grey circles shows the average value in Data Numbers for each of the individual 20 frames at each time step. There is an obvious outlier that lies above the other frames. This is the first image that was taken and is not used in the rest of the analysis. The dark circles in panel A. are the average at each time step of the 19 frames.
- Panel B. displays the average values at each time step divided by the integration time, resulting in a value of DNs per second, which appears to be fairly constant. Ignoring the first and last time step, the average value is 12.5 DN per second. *Note: not sure why the last read is off. Has this been seen before?*
- For panel C. I found the amount of light in the orders and compared it to the amount of light in between the orders. This analysis showed that, on average, the amount of light in between the orders is at the 3.5% level compared to the light in the orders.
1 comment:
We might want to check this again at a larger angle - say around 56 degrees. At 37 degrees, we are using both sides of the grooves, so may have different scattered light.
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