1. Every spectrometer has an instrument function 



and this function should be removed before attempting diagnostics 

 with the data. The interferometer spectrometer function closely 

 resembles that of tlie photoiaultiplier tube, alone, since there 

 are no dispersing elements. Hence, a "smooth" function results. 



2. Since instrument calibration corrections arc 

 required for quantitative spectroscopic studies, compute 

 reduction of the data is really the most advantageous route 

 to follow. Hence, the necessity of performing Fourier ticuis- 

 formations on the computer in the case of this class of instruments 

 poses no constraint since one v.'ould resort to the computer 



for the other corrections. 



The enclosed figures contain the computer reduced 

 spectra number's 19-26. All of these spectra were obtained in 



75 seconds v/ith attenuation factors ranging from apj^roximately 



5 7 

 10 to 10 . As you can see, the spectrometer was hardly taxed 



during the experiment. 



Spectra 19, 2 3 and 24 were talcen at the surface of the 



water using the m.odi f led light shield basket v;e brought. 



There v.'a s no gla'^^s bottoia on the basT-ret. ITenci:^, these thioc 



spectra measure the :>'.ero depth u];)welling irradiance at Eel 



Pond during tliis time period. The moasui: emcnts v.'ere talten 



at about an 80° depression fmglc loohing down into the water. 



29-3 



