CCD Photometry with Mathematica

Table of Contents

CCDPhotometry`Reduction`

This package contains functions for reducing CCD FITS data in preparation for data extraction.

AverageFrame[files]	Returns an average of FITS objects from a list of specified FITS objects.
SubtractFrame[file1, file2]	Subtracts the data of file2 from file1 and returns a new FITS object with the header of file1.
NormalizeFlat[file]	Assumes that file is a flat-field image and normalizes the field.
RemoveOverscan[file, {lb, ub}]	Removes the overscan region specified from lowerbound, lb, to upper bound, ub, from the FITS data, file.
FlatField[imagefile, biasfile, normflatfile]	Assumes that normflatfile is a normalized flat-field frame and divides the bias subtracted imagefile by the normflatfile.

Image Reduction for Files

AverageFrame[{imgobj1,...,imgobjn}]	Returns an average of FITS objects from a list of specified FITS objects.
SubtractFrame[imgobj1, imgobj2]	Subtracts the data of imgobj2 from imobj1 and returns a new FITS object with the header of imgobj1.
NormalizeFlat[imgobj]	Assumes that imgobj is a flat-field image and normalizes the field.
RemoveOverscan[imgobj, {lb, ub}]	Removes the overscan region specified from lowerbound, lb, to upper bound, ub, from the FITS data, imgobj.
FlatField[imageobj, biasobj, normflatobj]	Assumes that normflatfobj is a normalized flat-field frame and divides the bias subtracted imageobj by the normflatobj.

Image Reduction for FITS Objects

This loads the package.

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This loads packages for reading images and displaying them.

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Now we load the image, bias, and flat-field frames

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rawimg = ImageLoad[ToFileName["CCDPhotometry", "May08_0132.fit"]]

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bias = ImageLoad[ToFileName["CCDPhotometry", "avgbias.fit"]]

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rawvflat = ImageLoad[ToFileName["CCDPhotometry", "avgvflat.fit"]]

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We can view them

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Show[GraphicsArray[{DisplayImage[img, DisplayFunctionIdentity], DisplayImage[bias, D ... layFunctionIdentity]}], DisplayFunction$DisplayFunction, ImageSize500] ;