anchor.diff:        integer, parameter :: model=5 ! 5: subarctic winter
         integer, parameter :: itype=3 ! 3: vertical or slant path to space
         integer, parameter :: iemsct=0! 0: transmittance model
  +      real, parameter :: ANGLE=0. ! initial zenith angle; in Python set to camera boresight angle (for our cameras typically magnetic inclination of E-layer ionosphere, e.g. angle is about 12.5 at Poker Flat Research Range)
  +      
  +      real, parameter :: h1=0. ! our cameras are at ground level (kilometers)
   ! in lowtran7.f, I set M1-M6, MDEF all =0 per p.21
   
   !!! Horizontal model (only way to use meterological data) !!!
  
positive.code:       real, Parameter :: v1=8333., v2=33333. ! frequency cm^-1 bounds
        ! DV: frequency cm^1 step (lower limit 5. per Card 4 p.40)
        real, parameter :: dv=500. 
  ! Model configuration, see Lowtran manual p. 21(30) s. 3.2
  ! Use only one of the following model scenarios
  
  
negative.code: !      integer, parameter :: iemsct=0! 0: transmittance model
  ! TODO M1-M6=0 to use JCHAR of card 2C.1 (p.22)
  
  !      real, parameter :: h1 = 0.05  (kilometers altitude of horizontal path)
  !      real, parameter :: angle = 0. ! TODO truthfully it's 90. for horizontal path, have to check/test to see if Lowtran uses this value for model=0
  !-------- END model config -----------------
  
  !-------- array assignments --------
          Real :: TXPy(nwl,ncol), VPy(nwl), ALAMPy(nwl), TRACEPy(nwl),
       &      UNIFPy(nwl), SUMAPy(nwl)
  
          call LWTRN7(Python,nwl,V1,V2,DV,
       &  TXPy,VPy,ALAMPy,TRACEPy,UNIFPy, SUMAPy,
  