SYNFTACH (Feb93)                  model                 SYNFTACH (Feb93)



NAME
    synftach
    
    
USAGE
    synftach imprfx x0 y0 rsun imvim nx ny br0 amf
        imdphi ang_intf v0 flam0 dlam0 imspndb imfrndb
        ang_det imgain imdark nfc cyfrac sumn delete print
        mbytes
    
    
PARAMETERS
    
    imprfx
        Prefix  that  is  used  to generate image file names for working
        files and the final output.
    
    x0                                      
        x-coord of the center of the image in pixels.
    
    y0                                          
        y-coord of the center of the image in pixels.
    
    rsun                          
        Radius of the image in pixels.
    
    imvim                           
        Input image name for velocity, intensity,  modulation.   If  not
        supplied,  the parameters below (NX,NY,BR0,AMF) must be supplied
        to generate the VIM image.
    
    nx                          
        1st dimension of the images.
    
    ny                             
        2nd dimension of the images.
    
    br0                                                          
        Central solar brightness in ADU.
    
    amf                             
        Average modulation fraction at disk center.
    
    imdphi                                
        2D input image containing the interferometer phase distortion.
    
    ang_intf                              
        Interferometer rotation angle in deg.
    
    v0                                         
        Velocity for zero phase of interferometer in m/s.
    
    flam0                                      
        Solar spectrum line wavelength in Angstroms.
    
    dlam0                                
        Free spectral range of the interferometer in Angstroms.
    
    imspndb                               
        3D  input  image  containing  the  numerator,  denominator,  and 
        brightness components of the spurious modulation.
    
    imfrndb                             
        3D  input image containing the 3 fringe contrasts for numerator,
        denominator, and brightness.
    
    ang_det                          
        Detector rotation angle in deg.
    
    imgain                              
        2D input image containing the detector gain.
    
    imdark                                     
        2D input image containing the detector dark current.
    
    nfc                                       
        3rd Dimension  of  the  output  images;  no.  of  interferometer
        phases.
    
    cyfrac                          
        Camera readout cycle fraction.
    
    sumn                            
        Sample sum parameter.
    
    delete                          
        Delete intermediate files?
    
    print                       
        print?
    
    mbytes
        Available memory for image pixel arrays in Megabytes.
        This  parameter  can  be  used  to control the amount of virtual
        memory paging that will occur if all the  pixel  arrays  do  not
        fit into the available real memory.
    
    
IMAGE HEADER WORDS
    
    The  three  image  dimension parameters for the output image are set
    from the input parameters:  NX, NY, NFC.
    
    The following parameters are written to the output image header:
    
        PIXLENX=1.0
        the x-direction size of the camera pixels
    
        PIXLENY=1.0
        the y-direction size of the camera pixels
    
        FNDLMBXC = X0, an input parameter
        x coordinate of the center of the disk in pixels
    
        FNDLMBYC = Y0, an input parameter
        y coordinate of the center of the disk in pixels
    
        FNDLMBMI = RSUN, an input parameter
        length of the semiminor axis in pixels
    
        FNDLMBMA = RSUN, an input parameter
        length of the semimajor axis in pixels
    
        FNDLMBAN = 0.0
        angle between the semimajor axis and the y axis in degrees
    
    
DESCRIPTION
    
    SYNFTACH is a script that uses GENVIM, RROTAT,  INTERF,  and  DETECT
    to compute the response of a Fourier tachometer.
    
    SYNFTACH  is  from  Tim  Brown's  Fourier  tachometer modeling code,
    "FAKEFT".
    
    
EXAMPLES
    
    
TIME REQUIREMENTS
    
    
BUGS
    
    
SEE ALSO
    genvim
    rrotat
    interf
    detect