#

The sequence number of the measurement.

Image

The name of the image that was measured

Obj

The label of the object. This is a sequential number.

Name

A name for the object. The default name is created by combining a prefix with a sequential number (see Default Name Prefix in the Other Properties page). You can override the default name using the Edit mode from the Aperture Photometry Toolbar. See Using Edit Mode in Aperture Photometry.

Magn

The measured or computed magnitude.

• If the photometric zero point does not exist, this is a raw magnitude with a value less than 0.

• If the zero point exists, this is a positive number.

Std?

This column has an * if the object is a Standard.

Error

The Empirical estimate of the magnitude uncertainty (mean error) based on sky noise measurements. See Photometric Error Definitions.

Error(T)

The theoretical estimate of the magnitude uncertainty (mean error). Especially for faint objects, Error(T) is more stable than the empirically measured Error, and it provides a reference value for comparison with the noisy Error value. See Photometric Error Definitions.

X

The X coordinate of the object. If the image has a WCS calibration, this is right ascension, otherwise this is the column coordinate.

Y

The Y coordinate of the object. If the image has a WCS calibration, this is declination, otherwise this is the row coordinate.

Col

The column coordinate of the object.

Row

The row coordinate of the object.

Backgr

The estimate of local background

S/N

The Signal to Noise Ratio of the detection, including the background.

Mag Std

The magnitude of the standard star. This is the value entered by you or imported from a catalog file.

Resid

For Standards, the magnitude residual from the zero point calculation.

Net Count

The net count above the background value. This value includes the exact number of partial pixels inside the object aperture.

Ap Sum

The total count inside the inner (object) aperture. This value does not account for the background and may be used to compute the magnitude using alternate background statistics, such as tne sigma clipped mean value nearby. See Statistics Measurements.

Like the Net Count, the Ap Sum includes the exact number of partial pixels inside the object aperture. See Magnitude Calculations.

Filter

The filter used for the image, take from the FILTER keyword in the header.

Date

The date of observation, from the DATE-OBS header keyword, in GMT

Time

The time of observation, from the TIME-OBS (or DATE-OBS) header keyword, GMT, modified by the exposure time and the time stamp property . The reported time may correspond to the beginning, middle, or end of the exposure, See the discussion of PTIMEREF under Airmass Calculation, below.

JD, HJD, MJD, or MHJD

The type of Julian Date is selected using the Julian Date Type selector in the Other Properties dialog. See discussion of PTIMEREF under Airmass Calculation, below. This also may include a date offset as entered on the Other Properties page.

The ordinary geocentric Julian Date, JD or MJD, is calculated from the Date and Time. The heliocentric Julian Date, HJD of MHJD, also involve the Right Ascension and Declination of the observation.

The Heliocentric Julian Date calculated by Mira is extremely consistent results from with a high quality online Julian Date reference calculator. Based on 14 comparisons between calculations, the average difference in HJD is about 0.01 seconds, with a standard deviation of 0.57 seconds (1-sigma). See Mira's Heliocentric Julian Date Calculation.

Airmass

The airmass of the observation. A value of 0.0 indicates that the airmass could not be calculated. See the discussion below.

Exptime

The exposure time, in seconds, take from the EXPTIME header keyword.

Weight

For standard stars, the statistical weight used in calculating the photometric zero point.

Notes

Notes you add into the Standard Data or Target Data dialog in Edit mode using the Aperture Photometry toolbar. See Using Edit Mode in Aperture Photometry.