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sin(alt)=sin(dec)sin(lat) + cos(dec) cos(HA) cos(lat)
Sky Brightness from LSST ETC
FWHM of 0.87 at airmass=1.2 derived from FWHM=0.7 in r at zenith.
footprint is 26.82 pixels, Gaussian weighted. Units are electrons in 15 sec exposure. Moon is 90 deg from foresight
| lunar phase\filter | u | g | r | i | z | y4 |
|---|---|---|---|---|---|---|
| 0 | 42 | 89 | 111 | 159 | 218 | 238 |
| 3 | 53 | 107 | 113 | 159 | 218 | 238 |
| 7 | 81 | 160 | 140 | 174 | 224 | 238 |
| 11 | 143 | 280 | 205 | 215 | 242 | 242 |
| 14 | 240 | 474 | 305 | 269 | 263 | 254 |
| (bright/dark) ratio | 5.7 | 5.3 | 2.7 | 1.7 | 1.2 | 1.07 |
| SNR impact~sqrt(sky) | 2.4 | 2.3 | 1.6 | 1.3 | 1.1 | 1.03 |
Merit Function Ingredients.
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