//SexTractor-based method for getting the ADU of the star at the center of a trackbox subframe
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
AstroImage asti = new AstroImage
{
Camera = AstroImage.CameraType.Imaging,
SubFrame = 1,
Frame = AstroImage.ImageType.Light,
BinX = GuiderXBinning,
BinY = GuiderYBinning,
Delay = 0,
Exposure = exposure,
ImageReduction = AstroImage.ReductionType.AutoDark
};
TSXLink.Camera gCam = new TSXLink.Camera(asti)
{
AutoSaveOn = 1//Turn on autosave so we can extract a star inventory via ShowInventory()
};
//Compute the subframe from the trackbox size
int sizeX = gCam.TrackBoxX;
int sizeY = gCam.TrackBoxY;
gCam.SubframeTop = (int)GuideStarY - (sizeY / 2);
gCam.SubframeBottom = (int)GuideStarY + (sizeY / 2);
gCam.SubframeLeft = (int)GuideStarX - (sizeX / 2);
gCam.SubframeRight = (int)GuideStarX + (sizeX / 2);
//Take an image f
int tstat = gCam.GetImage();
if (tstat != 0)
{
return(0);
}
//Next step is to generate the collection of stars in the subframe
TSXLink.SexTractor sEx = new TSXLink.SexTractor();
bool xStat = sEx.SourceExtractGuider();
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);
//Find the star with the greatest FWHM
int iMax = sEx.GetListLargest(FWHMlist);
//Determine the ADU value at the center of this listed star.
// if it is zero, then look for the maximum pixel ADU
double maxStarADU = 0;
try
{
maxStarADU = sEx.GetPixelADU((int)CenterX[iMax], (int)CenterY[iMax]);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
maxStarADU = 0;;
}
if (maxStarADU == 0)
{
maxStarADU = gCam.MaximumPixel;
}
return(maxStarADU);
}
public static bool PickAutoGuideStar(GuideStarCriteria gsc)
{
// Subroutine takes a picture, picks a guide star, computes a subframe to put around it,
// loads the location and subframe into the autoguider
//
// The only difference in this procedure from SetBestAutoGuideStar is that it finds the largest FWHM star rather than
// the average, and this does not exclude prospects because they have neighbors.
// 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
//
double MagWeight;
double FWHMWeight;
double ElpWeight;
double ClsWeight;
bool CheckNeighbors;
// 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: round = 1
// Class optimal is highest class: 0 is galaxy, 1 is star
//
// Normalized means adjusted against the range of highest to lowest becomes 1 to 0, unless there is only one datapoint
//
//
AstroImage asti = new AstroImage
{
Camera = AstroImage.CameraType.Imaging,
SubFrame = 0,
Frame = AstroImage.ImageType.Light,
BinX = GuiderXBinning,
BinY = GuiderYBinning,
Delay = 0,
Exposure = GuideExposure,
ImageReduction = AstroImage.ReductionType.AutoDark
};
TSXLink.Camera guider = new TSXLink.Camera(asti)
{
AutoSaveOn = 1
};
//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
{
bool sStat = tsex.SourceExtractGuider();
}
catch (Exception ex)
{
// Just close up, TSX will spawn error window
MessageBox.Show("Star Extracdtion Error: " + ex.Message);
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)
{
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;
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];
}
avgFWHM /= starCount;
// Create a set of "best" values
double optMag; // Magnitudes increase with negative values
double optFWHM; // Looking for the closest to maximum FWHM
double optElp; // Want the minimum amount of elongation
double optCls; // 1 = star,0 = galaxy
//Set selection optimization based on criteria type (maybe more in the future)
switch (gsc)
{
case GuideStarCriteria.Clean:
optMag = minMag; // Magnitudes increase with negative values
optFWHM = avgFWHM; // Looking for the closest to average FWHM
optElp = minElp; // Want the minimum amount of elongation
optCls = maxCls; // Want closest to star: 1 = star,0 = galaxy
MagWeight = 1; //?Equal weighting
FWHMWeight = 1; //?Equal weighting
ElpWeight = 1; //?Equal weighting
ClsWeight = 1; //?Equal weighting
CheckNeighbors = true;
break;
case GuideStarCriteria.Big:
optMag = minMag; // Magnitudes increase with negative values
optFWHM = maxFWHM; // Looking for the closest to maximum FWHM
optElp = minElp; // Want the minimum amount of elongation
optCls = maxCls; // Want closest to star: 1 = star,0 = galaxy
MagWeight = 1; //?Equal weighting
FWHMWeight = 1; //?Equal weighting
ElpWeight = 0; //Don't care
ClsWeight = 0; //Don't care
CheckNeighbors = true;
break;
case GuideStarCriteria.Bright:
optMag = minMag; // Magnitudes increase with negative values
optFWHM = maxFWHM; // Looking for the closest to average FWHM
optElp = minElp; // Want the minimum amount of elongation
optCls = maxCls; // Want closest to star: 1 = star,0 = galaxy
MagWeight = 1; //?Equal weighting
FWHMWeight = 1; //Don't care
ElpWeight = 1; //Don't care
ClsWeight = 1; //Don't care
CheckNeighbors = true;
break;
default:
optMag = minMag; // Magnitudes increase with negative values
optFWHM = avgFWHM; // Looking for the closest to average FWHM
optElp = minElp; // Want the minimum amount of elongation
optCls = maxCls; // Want closest to star: 1 = star,0 = galaxy
MagWeight = 1; //?Equal weighting
FWHMWeight = 1; //?Equal weighting
ElpWeight = 1; //?Equal weighting
ClsWeight = 1; //?Equal weighting
CheckNeighbors = true;
break;
}
// 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;
double normPt;
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
normPt = ((normMag * MagWeight) + (normFWHM * FWHMWeight) + (normElp * ElpWeight) + (normCls * ClsWeight));
SourceCount += 1;
// Tentatively assign nomalized value array the normalized value
NormArr[i] = normPt;
// Remove neighbors and edge liers
edgekeepout = trackBoxSize;
if (IsOnEdge((int)XPosArr[i], (int)YPosArr[i], Xsize, Ysize, edgekeepout))
{
NormArr[i] = -1;
}
if (CheckNeighbors)
{
for (int j = i + 1; j < NormArr.Length - 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;
}
}
//Register the results
guider.GuideStarX = XPosArr[bestOne] * guider.BinX;
guider.GuideStarY = YPosArr[bestOne] * guider.BinY;
asti.SubframeLeft = (int)(XPosArr[bestOne] - (trackBoxSize / 2)) * guider.BinX;
asti.SubframeRight = (int)(XPosArr[bestOne] + (trackBoxSize / 2)) * guider.BinX;
asti.SubframeTop = (int)(YPosArr[bestOne] - (trackBoxSize / 2)) * guider.BinY;
asti.SubframeBottom = (int)(YPosArr[bestOne] + (trackBoxSize / 2)) * guider.BinY;
guider.SubframeLeft = asti.SubframeLeft;
guider.SubframeRight = asti.SubframeRight;
guider.SubframeTop = asti.SubframeTop;
guider.SubframeBottom = asti.SubframeBottom;
if (NormArr[bestOne] != -1)
{
GuideStarX = guider.GuideStarX;
GuideStarY = guider.GuideStarY;
tsex.Close();
return(true);
}
else
{
// Debug code: 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;
}
}
tsex.Close();
return(false);
}
}
