Other Properties (Photometry)
The Other Properties page is a member of the Aperture Photometry Properties dialog. This page has a number of important Properties that affect the aperture photometry process.
To open the Other Properties page, click on the Aperture Photometry toolbar and select the Other tab.
Table Properties |
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Background Method |
This list box chooses the mathematical method used to estimate the sky background level from pixels in the outer annulus. If there are contaminating objects in the background annulus, choose Modal Brightness, which does a good job of rejecting outlying values. If the fields of view is fairly sparse and it is unlikely that any objects contaminate the background annuli of the stars, the other 2 methods may be chosen. |
Exposure Time Reference |
This Properties selects the time stamp that goes into the Apphot Pane. The time of the observation is calculated from the date and time of observation from the image header and the exposure time, following the rule you select here. |
Julian Date Type |
Select the type of Julian Date to be reported in the photometry table. The options are Heliocentric JD, Geocentric (normal) JD, and Modified Julian Date for both heliocentric and geocentric forms. The selection is listed in the Photometry Report; see Photometric Measurement Definitions. |
Julian Date Offset |
Enter the value to subtract from Julian Date listed in the Apphot Measurement Pane. If desired, the number may be fractional, such as 2453000.5. After clicking[Apply] or [Save] the photometry report is updated with the new Julian Date including the offset. |
Drawing Mode |
This list box provides alternative ways of drawing the photometry markers on objects. |
Keywords |
Click this button to open the Photometry Keywords dialog. There you setup keyword names used by aperture photometry to load Properties from the image headers. |
Verbose Messages |
If checked, Mira lists verbose text messages about the photometric measurements. |
Zoom for GoTo |
Specifies the zoom factor for the Go to Object menu command of the photometry measurements grid. |
Scale to FWHM |
If checked, the apertures are scaled to multiples of the FWHM of the image. This setting requires that the FWHM have been measured and is stored in the image header using the PSF-FWHM keyword . |
Calculate Airmass |
If checked, the airmass is calculated for each image using header keywords specified in the Photometry Keywords dialog. If not checked, the airmass for each image is taken from the AIRMASS keyword in the image header.
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Include Zero Point Error |
Check this box to include the uncertainty (error) in the photometric zero point to the internal error of the measurement. If checked, the reported errors include these two error terms added as the root sum of squares. If you change the check box after measurements are made, click to recalculate the errors in the Apphot Pane. |
Default Name Format |
Enter the Prefix to use for the names of marked stars. A number is appended to this entry to make the default name for each marked object. However, the default name can be overridden using the Edit button on the toolbar. Use the [+] and [x] buttons to add or delete the currently displayed entry. |
Aperture Photometry, Aperture Photometry Properties, Photometry Keywords