Detector Counts Need Calibration

Dark Count Subtracts

net signal comes first

A fixed dark baseline is removed before calibration. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

The detector reports a measured count

The measured detector count is 15 and the dark baseline is 3.

Cmeasured=15,Cdark=3C_{\text{measured}}=15,\quad C_{\text{dark}}=3
Detector calibrationBaseline and gain set the reported signal.measureddarknetoutput1531212

Subtract the dark baseline first

The net signal is 12. The dark count is fixed here, not random noise.

Cnet=15 minus 3=12C_{\text{net}}=15\text{ minus }3=12
Detector calibrationBaseline and gain set the reported signal.measureddarknetoutput1531212