Understanding Counts in Spectrometer

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The discussion centers on using the Ocean Optics USB4000 spectrometer to measure light in aquariums, with data output in counts across various wavelengths. The user is confused about the meaning of negative counts and how to convert these measurements into optical units. It is suggested that negative values may indicate background subtraction, and if they are negative, calibration issues could be present. The user seeks clarification on the conversion factors needed for meaningful analysis. Proper calibration and understanding of the spectrometer's output are essential for accurate data interpretation.
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Well, I'm not a physician so, maybe my doubt is a little fool. Well, I'm mapping the light emitted by some lamps in some aquariums. For that, I'using a spectrometer named Ocean Optics USB4000 and a software named SpectraSuite. My intention is to discover how much is the total light getting into the aquariums and haw is it distributed in the aquarium. After taking the measurements, i will interpolate the data in the software Voxler from goldensoftware.
Well, my problem is in the beginning of these processes: the data that the spectrometer take is given by counts in each kind of wave, like that:
Wave Counts
178,91 -30,32
179,13 -30,32
179,34 -30,32
179,56 -47,11
179,78 -52,23
180,00 25,59
180,21 -3,29
180,43 4,70
180,65 56,92
180,86 -16,19
181,08 4,13
181,30 6,32
181,51 10,22
181,73 13,86
181,95 18,10
182,17 22,35
182,38 22,55
182,60 23,71
182,82 24,45
183,03 21,25
183,25 23,55
183,47 23,24
183,68 25,75
183,90 26,41
184,12 26,91
184,34 26,41
184,55 29,11
184,77 29,52
184,99 30,15
185,20 31,23
185,42 31,96
185,64 31,48
(......)
880,40 239,06
880,57 228,80
880,74 222,27
880,91 213,25
881,07 207,39
881,24 199,64
881,41 191,34
881,58 185,91
881,74 182,21
881,91 176,63
882,08 170,85
882,25 165,77
882,42 163,48
882,58 161,57
882,75 159,43
882,92 158,30
883,09 158,19
883,25 156,41
883,42 155,53
883,59 154,07
883,76 150,13
883,92 149,86
884,09 150,75
884,26 147,37
884,43 148,47
884,60 147,10
884,76 147,05
884,93 147,07
885,10 145,44
885,27 145,20
885,43 144,78
885,60 145,16
885,77 143,63
885,93 142,32
886,10 142,19
886,27 143,42
886,44 142,82
886,60 142,32
886,77 143,33
886,94 143,85
887,11 142,79
887,27 146,86
887,44 148,05
887,61 148,53
887,77 153,58
887,94 157,17
888,11 145,19
888,28 145,60
888,44 154,82
888,61 164,44
888,78 136,79
888,94 203,56
889,11 196,60
889,28 169,77
889,45 229,98
889,61 215,23

As you can see, there are even negative counts and I'm not getting really well what is the meaning of these "counts" and how can i convert it to any optic unites.
 
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That is something the manual should show. There should be some conversion factor between counts and some more useful unit.

Negative values suggest the device subtracts some background, if the result is negative some calibration might have gone wrong.
 
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