//SexTractor-based method for getting the ADU of a guide star
public static double GetGuideStarADU(double exposure)
{
//Determines the ADU for the X/Y centroid of the maximum FWHM star in a subframe
//
//Take a subframe image on the guider using TSX guide star coordinates and trackbox size
LogEvent lg = new LogEvent();
SessionControl openSession = new SessionControl();
TargetPlan tPlan = new TargetPlan(openSession.CurrentTargetName);
lg.LogIt("Creating Guider Subframe Image");
AstroImage asti = new AstroImage
{
Camera = AstroImage.CameraType.Guider,
SubFrame = 1,
Frame = AstroImage.ImageType.Light,
BinX = tPlan.GuiderBinning,
BinY = tPlan.GuiderBinning,
Delay = 0,
Exposure = exposure
};
//Set image reduction
if (tPlan.GuiderAutoDarkEnabled)
{
asti.ImageReduction = AstroImage.ReductionType.AutoDark;
}
else
{
asti.ImageReduction = AstroImage.ReductionType.None;
}
TSXLink.Camera gCam = new TSXLink.Camera(asti)
{
AutoSaveOn = 1//Turn on autosave so we can extract a star inventory via ShowInventory()
};
//Center up AO, just in case and if enabled
if (tPlan.AOEnabled)
{
gCam.CenterAO();
}
//Compute the subframe from the trackbox size
int sizeX = gCam.TrackBoxX;
int sizeY = gCam.TrackBoxY;
gCam.SubframeTop = (int)(tPlan.GuideStarY * tPlan.GuiderBinning) - (sizeY / 2);
gCam.SubframeBottom = (int)(tPlan.GuideStarY * tPlan.GuiderBinning) + (sizeY / 2);
gCam.SubframeLeft = (int)(tPlan.GuideStarX * tPlan.GuiderBinning) - (sizeX / 2);
gCam.SubframeRight = (int)(tPlan.GuideStarX * tPlan.GuiderBinning) + (sizeX / 2);
//Take an image f
int tstat = gCam.GetImage();
if (tstat != 0)
{
lg.LogIt("Autoguider Image Error: " + tstat.ToString());
return(0);
}
lg.LogIt("Guider Subframe image successful");
//Next step is to generate the collection of stars in the subframe
TSXLink.SexTractor sEx = new TSXLink.SexTractor();
int xStat = sEx.SourceExtractGuider();
lg.LogIt("Light source extraction complete");
List <double> FWHMlist = sEx.GetSourceExtractionList(TSXLink.SexTractor.SourceExtractionType.sexFWHM);
List <double> CenterX = sEx.GetSourceExtractionList(TSXLink.SexTractor.SourceExtractionType.sexX);
List <double> CenterY = sEx.GetSourceExtractionList(TSXLink.SexTractor.SourceExtractionType.sexY);
int iMax = sEx.GetListLargest(FWHMlist);
double maxStarADU = 0;
try
{
maxStarADU = sEx.GetPixelADU((int)CenterX[iMax], (int)CenterY[iMax]);
}
catch (Exception ex)
{
lg.LogIt("Light Source error -- no stars?");
}
if (maxStarADU == 0)
{
maxStarADU = gCam.MaximumPixel;
}
return(maxStarADU);
}
//*** SetAutoGuideStar picks a guide star and places a subframe around it
public static bool SetAutoGuideStar()
{
// Subroutine takes a picture, picks a guide star, computes a subframe to put around it,
// loads the location and subframe into the autoguider
//
// Subroutine picks a guide star, computes a subframe to put around it based on current TSX settings
// and loads the location and subframe into the autoguider
//
int MagWeight = 1;
int FWHMWeight = 1;
int ElpWeight = 1;
int ClsWeight = 1;
// Algorithm:
//
// Compute optimality and normalizaton values (see below)
// Eliminate all points near edge and with neighbors
// Compute optimality differential and normalize, and add
// Select best (least sum) point
//
// Normalized deviation from optimal where optimal is the best value for each of the four catagories:
// Magnitude optimal is lowest magnitude
// FWHM optimal is average FWHM
// Ellipticity optimal is lowest ellipticity
// Class optimal is lowest class
//
// Normalized means adjusted against the range of highest to lowest becomes 1 to 0, unless there is only one datapoint
//
//
LogEvent lg = new LogEvent();
SessionControl openSession = new SessionControl();
TargetPlan tPlan = new TargetPlan(openSession.CurrentTargetName);
lg.LogIt("Finding guide star coordinates");
AstroImage asti = new AstroImage
{
Camera = AstroImage.CameraType.Guider,
SubFrame = 0,
Frame = AstroImage.ImageType.Light,
BinX = tPlan.GuiderBinning,
BinY = tPlan.GuiderBinning,
Delay = 0,
Exposure = tPlan.GuideExposure
};
//Set image reduction
if (tPlan.GuiderAutoDarkEnabled)
{
asti.ImageReduction = AstroImage.ReductionType.AutoDark;
}
else
{
asti.ImageReduction = AstroImage.ReductionType.None;
}
TSXLink.Camera guider = new TSXLink.Camera(asti)
{
AutoSaveOn = 1
};
//Center AO, if configured
if (tPlan.AOEnabled)
{
guider.CenterAO();
}
//Take an image f
int camResult = guider.GetImage();
//acquire the current trackbox size (need it later)
int TrackBoxSize = guider.TrackBoxX;
TSXLink.SexTractor tsex = new TSXLink.SexTractor();
try
{
int sStat = tsex.SourceExtractGuider();
}
catch (Exception ex)
{
// Just close up, TSX will spawn error window
lg.LogIt("Some problem with guider image: " + ex.Message);
tsex.Close();
return(false);
}
int Xsize = tsex.WidthInPixels;
int Ysize = tsex.HeightInPixels;
// Collect astrometric light source data from the image linking into single index arrays:
// magnitude, fmhm, ellipsicity, x and y positionc
//
double[] MagArr = tsex.GetSourceExtractionArray(TSXLink.SexTractor.SourceExtractionType.sexMagnitude);
int starCount = MagArr.Length;
if (starCount == 0)
{
lg.LogIt("No astrometric sources found");
tsex.Close();
return(false);
}
double[] FWHMArr = tsex.GetSourceExtractionArray(TSXLink.SexTractor.SourceExtractionType.sexFWHM);
double[] XPosArr = tsex.GetSourceExtractionArray(TSXLink.SexTractor.SourceExtractionType.sexX);
double[] YPosArr = tsex.GetSourceExtractionArray(TSXLink.SexTractor.SourceExtractionType.sexY);
double[] ElpArr = tsex.GetSourceExtractionArray(TSXLink.SexTractor.SourceExtractionType.sexEllipticity);
double[] ClsArr = tsex.GetSourceExtractionArray(TSXLink.SexTractor.SourceExtractionType.sexClass);
// Get some useful statistics
// Max and min magnitude
// Max and min FWHM
// Max and min ellipticity
// max and min class
// Average FWHM
double maxMag = MagArr[0];
double minMag = MagArr[0];
double maxFWHM = FWHMArr[0];
double minFWHM = FWHMArr[0];
double maxElp = ElpArr[0];
double minElp = ElpArr[0];
double maxCls = ClsArr[0];
double minCls = ClsArr[0];
double avgFWHM = 0;
double avgMag = 0;
for (int i = 0; i < starCount; i++)
{
if (MagArr[i] < minMag)
{
minMag = MagArr[i];
}
if (MagArr[i] > maxMag)
{
maxMag = MagArr[i];
}
if (FWHMArr[i] < minFWHM)
{
minFWHM = FWHMArr[i];
}
if (FWHMArr[i] > maxFWHM)
{
maxFWHM = FWHMArr[i];
}
if (ElpArr[i] < minElp)
{
minElp = ElpArr[i];
}
if (ElpArr[i] > maxElp)
{
maxElp = ElpArr[i];
}
if (ClsArr[i] < minCls)
{
minCls = ClsArr[i];
}
if (ClsArr[i] > maxCls)
{
maxCls = ClsArr[i];
}
avgFWHM += FWHMArr[i];
avgMag += MagArr[i];
}
avgFWHM /= starCount;
avgMag /= starCount;
// Create a set of "best" values
double optMag = minMag; // Magnitudes increase with negative values
double optFWHM = avgFWHM; // Looking for the closest to maximum FWHM
double optElp = minElp; // Want the minimum amount of elongation
double optCls = maxCls; // 1 = star,0 = galaxy
// Create a set of ranges
double rangeMag = maxMag - minMag;
double rangeFWHM = maxFWHM - minFWHM;
double rangeElp = maxElp - minElp;
double rangeCls = maxCls - minCls;
// Create interrum variables for weights
double normMag;
double normFWHM;
double normElp;
double normCls;
// Count keepers for statistics
int SourceCount = 0;
int EdgeCount = 0;
int NeighborCount = 0;
int edgekeepout;
// Create a selection array to store normilized and summed difference values
double[] NormArr = new double[starCount];
// Convert all points to normalized differences, checking for zero ranges (e.g.single or identical data points)
for (int i = 0; i < starCount; i++)
{
if (rangeMag != 0)
{
normMag = 1 - Math.Abs(optMag - MagArr[i]) / rangeMag;
}
else
{
normMag = 0;
}
if (rangeFWHM != 0)
{
normFWHM = 1 - Math.Abs(optFWHM - FWHMArr[i]) / rangeFWHM;
}
else
{
normFWHM = 0;
}
if (rangeElp != 0)
{
normElp = 1 - Math.Abs(optElp - ElpArr[i]) / rangeElp;
}
else
{
normElp = 0;
}
if (rangeCls != 0)
{
normCls = 1 - Math.Abs(optCls - ClsArr[i]) / rangeCls;
}
else
{
normCls = 0;
}
// Sum the normalized points, weight and store value
NormArr[i] = (normMag * MagWeight) + (normFWHM * FWHMWeight) + (normElp * ElpWeight) + (normCls * ClsWeight);
SourceCount += 1;
// Remove neighbors and edge liers
edgekeepout = openSession.GuideStarEdgeMargin;
if (IsOnEdge((int)XPosArr[i], (int)YPosArr[i], Xsize, Ysize, edgekeepout))
{
NormArr[i] = -1;
}
else
{
for (int j = i + 1; j < starCount - 1; j++)
{
if (IsNeighbor((int)XPosArr[i], (int)YPosArr[i], (int)XPosArr[j], (int)YPosArr[j], TrackBoxSize))
{
NormArr[i] = -2;
}
}
}
}
// Now find the best remaining entry
int bestOne = 0;
for (int i = 0; i < starCount; i++)
{
if (NormArr[i] > NormArr[bestOne])
{
bestOne = i;
}
}
guider.GuideStarX = XPosArr[bestOne] * asti.BinX;
guider.GuideStarY = YPosArr[bestOne] * asti.BinY;
asti.SubframeLeft = (int)(XPosArr[bestOne] - (TrackBoxSize / 2)) * asti.BinX;
asti.SubframeRight = (int)(XPosArr[bestOne] + (TrackBoxSize / 2)) * asti.BinX;
asti.SubframeTop = (int)(YPosArr[bestOne] - (TrackBoxSize / 2)) * asti.BinY;
asti.SubframeBottom = (int)(YPosArr[bestOne] + (TrackBoxSize / 2)) * asti.BinY;
if (NormArr[bestOne] != -1)
{
tPlan.GuideStarX = guider.GuideStarX / asti.BinX;
tPlan.GuideStarY = guider.GuideStarY / asti.BinY;
lg.LogIt("Guide star coordinates set");
tsex.Close();
return(true);
}
else
{
// run statistics -- only if (total failure
for (int i = 0; i < SourceCount; i++)
{
if (NormArr[i] == -1)
{
EdgeCount += 1;
}
if (NormArr[i] == -2)
{
NeighborCount += 1;
}
}
lg.LogIt("No Guide star found out of " +
SourceCount.ToString() + " stars, " +
NeighborCount.ToString() + " had neighbors and " +
EdgeCount.ToString() + " were on the edge.");
lg.LogIt("No Guide star coordinates set");
tsex.Close();
return(false);
}
}