Measurement Properties

bVerbose

Controls whether the measurement is silent or lists verbose information. Defaults to false (silent).

bRemoveBg

Controls whether the background value is removed from the raw measurement. This value defaults to true. The background parameters are set using the SetBgMethod method.

bCalcInstMag

Controls whether the instrumental magnitude is calculated from the net count. If this parameter is set to false, the Measure method sets returns a value in nNetCount but does not set nMag. This member defaults to true.

bApplyZeroPt

Controls whether the photometric zero point (the nZeroPt member) is used to return an instrumental magnitude in the nMag member. The default setting is true, which applies the zero point.

Instrumental Properties

nGain

The camera gain, measured in electrons per Count, or electrons per ADU (default 1.0). This value may be retrieved from the image using CImage:Gain method, or it can be automatically set using the GetImageParams method.

nReadNoise

The image readout noise, measured in electrons (default 1.0). This value may be retrieved from the image using CImage:KwdGetNum("RDNOISE") or CImage:KwdGetNumEx("RDNOISE"), or it can be automatically set using the GetImageParams method.

nExptime

The image exposure time, measured in seconds (default 1.0). This value may be retrieved from the image using the CImage:Exptime method, or it can be automatically set using the GetImageParams method.

nZeroPt

The photometric zero point for the image, measured in magnitudes (default 0.0). This value may be retrieved from the image using CImage:KwdGetNum("ZERO-PT") or CImage:KwdGetNumEx("ZERO-PT"), or it can be automatically set using the GetImageParams method.

nZeroPtErr

The uncertainty of the photometric zero point for the image, measured in magnitudes (default 0.0). You can assign the value or retrieve it from the image using CImage:KwdGetNum("ZEROPERR") or CImage:KwdGetNumEx("ZEROPERR").

Aperture Properties

nRadius1

The radius of the object measuring aperture, measured in pixels (default 3).

nRadius2

The radius of the inner background measuring aperture, measured in pixels (default 10).

nRadius3

The radius of the outer background measuring aperture, measured in pixels (default 16).

nEllipticity

The ellipticity of the aperture set (default 0, or circular). This measures the value 1 - b/a, where a is the semimajor axis and b is the semiminor axis of an ellipse. A circle has a = b.

nTheta

The angle of the semimajor axis of the aperture set (default 0). This is relevant only when elliptical apertures are used by setting a value of nEllipticity > 0.

nX

The X position of the center of the measure apertures, measured in pixel coordinates. This value also can be fetched using the class method X.

nY

The Y position of the center of the measure apertures, measured in pixel coordinates. This value also can be fetched using the class method Y.

nStatusCode

An integer number indicating the status returned by the GetImageParams method. This value also can be fetched using the class method GetStatusCode.

sErrMsg

Used by the Measure method to indicate "Success" or an error message. The error message also can be fetched using the class method GetErrMsg.

nNetCount

The net count for the object, measured in counts (or "ADU" or "DN"). If the bRemoveBg flag is true, this is the net count above the background. Otherwise, it is the total count above zero. This value also can be fetched using the class method NetCount.

nNetCountErr

The uncertainty in the net count for the object, measured in counts (or "ADU" or "DN"). This value is based on the background noise and photon statistics. This value also can be fetched using the class method NetCountErr.

nNetCountErrT

The theoretical uncertainty in the net count for the object, measured in counts (or "ADU" or "DN"). This value is based on instrumental parameters and photon statistics. This value also can be fetched using the class method NetCountErrT.

nBgValue

The background value per pixel, measured in counts (or "ADU" or "DN"). If the bRemoveBg flag is true, this value was subtracted from the total to calculate nNetCount. This value also can be fetched using the class method BgValue.

nBgValueErr

The error in the background value (per pixel). This is a 1-sigma mean error, not the error of the mean background. The value is measured in units of counts (or "ADU" or "DN"). If the bRemoveBg flag is true, this value was subtracted from the total count to calculate nNetCount. This value also can be fetched using the class method BgValueErr.

nMag

The measured magnitude of the object. If the bApplyZeroPt flag was true, then this includes the photometric zero point set in the nZeroPt value. This value also can be fetched using the class method Mag.

nMagErr

The random error in the value of nMag as calculated from the noise measured in the background sample. This value also can be fetched using the class method MagErr. To include the uncertainty of the photometric zero point in this returned error, specify a non zero vbalue for nZeroPtErr.

nMagErrT

The random error in the value of nMag as calculated using only the instrumental values( instead of the noise measured in the background sampl). This value also can be fetched using the class method MagErrT. To include the uncertainty of the photometric zero point in this returned error, specify a non zero vbalue for nZeroPtErr.

nSnRatio

The Signal to Noise Ratio of the signal measured inside the object aperture of radius nRadius1. This value is computed from the total signal and the signal error included in nMagErr. This value also can be fetched using the class method SNR

nSnRatioT

The Signal to Noise Ratio of the signal measured inside the object aperture of radius nRadius1. This value is computed from the total signal and the theoretical signal error included in nMagErrT. This value also can be fetched using the class method SNRT.