(*TEST* flat inverted) --- filter V, bin 2, night 210915, compared to previous night 210814, sigma = 0.0068 --- (flat / previous inverted)(flat inverted) --- filter B, bin 2, night 210809(flat inverted) --- filter SG, bin 2, night 210902(flat inverted) --- filter SI, bin 2, night 210914(flat inverted) --- filter SR, bin 2, night 210902(flat inverted) --- filter V, bin 2, night 210915