Optical channel captures are deterministic indexed exposures. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Channels are optical exposure settings
There are 4 fields and 3 optical channels.
Nfields=4,Nchannels=3
Captures multiply fields by channels
The capture count is 12. This is not spectral unmixing.