To initiate the photometric reduction of your Science images, including the generation of photometric reports (e.g., AAVSO report) and the visualization of Light Curves, access the Photometry dialog box by selecting Photometry from the Photometry menu.
Within the Photometry dialog box, you will provide essential input folders and specify output folders required for the photometric reduction process. Detailed explanations for these settings are provided below.
The dialog box is organized into five main sections: Input set, Output results, Photometry progress, Options and a set of command buttons.
Input set
- Click the button with three dots (...) beside the Folder with (incoming) Science images field to select the folder containing the Science images for photometric reduction. Science images within subfolders of the selected directory will also be considered during the photometric reduction process.
- Additionally, specify the name of the Calibration group to be utilized by clicking the button with the three dots next to the Calibration group field. Phoranso will create calibrated images for each Science image by selecting the appropriate master bias, dark and flat frames from the designated Calibration group.
It is important to mention that this step is unavailable if the Skip image calibration option is chosen.
Output results
Phoranso generates various output folders as part of its photometric reduction process. These folders are organized as subfolders within the directory housing your science images.
- The calibrated images output folder contains the calibrated images corresponding to each science image. You have the flexibility to assign a name to this subfolder. In our example, the default name Calibrated is used.
- During image calibration, Phoranso selects one master bias, dark and flat image from the Calibration group to calibrate each science image. The extracted master images are stored in a designated subfolder. This ensures continued access to the master frames, providing convenience for users who may revisit their science image folder after an extended period. In our example, the default name Masterfiles is used.
- At the end of the photometric reduction process, Phoranso generates Report files. A report file is created for each variable star present in your Science images, provided a corresponding Variable ID Card exists in the Variable Star Database. Each report file contains the observations derived from your science images, i.e. one line for each succeeded observation. In the example, the default folder name Reports is used.
- Throughout the photometric reduction, Phoranso utilizes a fixed-name Memory folder to store intermediate files. These files enable a user to resume photometry for one or more Science folders at any given moment without the need for Phoranso to reprocess images that have already undergone the photometric pipeline.
Photometry progress
The Photometry progress section provides real-time updates on the ongoing photometric reduction process. It includes the following fields:
- Successfully processed: indicates the number of Science images that have been succesfully photometrically processed.
- Failed: displays the number of Science images that encountered issues during photometry. Failures may result from problems such as astrometric solving difficulties, absence of target or reference stars, excessively blurry images, and more.
- To be processed: represents the number of Science images currently awaiting processing in the photometry pipeline.
- Remaining time: Phoranso estimates the remaining time to process the pending images in the photometry pipeline. This estimate is calculated after an initial set of science images has been processed and is continually refined throughout the reduction process.
Options
The Options section provides the following configuration fields:
- Live mode - create Reports if no new Science images:
- if not selected, Phoranso operates in the default Static Photometry mode, where the folder with Science images remains static once the photometric reduction has started, i.e. no new Science images should be added.
- When selected, Phoranso switches to Live mode, allowing the addition of new Science images during photometric reduction. As long as new Science images are added, the photometric reduction will continue.
Live mode is especially valuable if you run Phoranso during a night of observation while actively acquiring new Science images. When your observation session concludes, Phoranso will have generated light curves and reports for all observed variables.
When Live mode is selected, set the maximum duration of inactivity (in minutes). If no new Science images are received within the specified interval, Phoranso interprets the observing session as finished. It halts the photometric reduction process and generates the corresponding photometry reports.
- Clean Photometric Memory after Reports generation: automatically cleans the Memory folder, where intermediate files are stored during photometric reduction. Cleaning is done after generating the photometric reports.
- Skip image calibration: if Science images have been pre calibrated, selecting this option skips the calibration step. The specified Calibration group in the Input set is disregarded.
- Choose Log errors only to limit the contents of the logging window (see below) to error messages encountered during photometric reduction.
- Selecting Show FITS image will display each FITS image being processed in a dedicated FITS window. Additionally, aperture rings will be drawn around each target star and all reference, check, and comparison stars.
Command buttons
- Start/Resume Photometry: once all Input set parameters, Output results parameters, and Options have been set, click this button to initiate the photometric reduction of the Science images. The green-colored window located above the command buttons indicates the progress made during each step of the Photometry process.
- Stop Photometry: this button is active while photometry is ongoing. Click it to abort the ongoing photometric reduction. You can resume from where you left off by clicking the Start/Resume Photometry button again.
- Show Log File: the button opens a Logging window providing detailed information about the progress of the Photometry. It conveniently shows error messages for target stars whose photometry fails, for instance because the target or reference star is too close to the image border.
- Show Light Curves: allows the display of Light curve windows for target stars found during Photometry. This buttons becomes active after Photometry has started.
It also allows the display of Light curve windows while the photometry is still ongoing. You will see more and more observations being added to the Light curve windows as the photometric reduction progresses. Light curve windows are discussed in the next section.
- Create Reports: click this button to start the generation of photometric reports. It creates one report for each target star found during photometry. The type of report to be generated is selected in the Report Settings dialog box. Even if you Stop Photometry while not all Science images have been reduced, you can still create intermediate reports.
Concurrently reduce several sets of Science images
Phoranso introduces a distinctive feature that allows you to concurrently perform photometric reductions on multiple sets of Science images. For instance, if you have acquired science images for two target stars, you can simultaneously process these images for both stars.
This is achieved by initiating a second Photometry dialog box, while the photometric reduction of the first target star is ongoing. In this additional Photometry dialog box, you simply input the folder with Science images for the second target star. Phoranso will then continue the photometric reduction for both stars in parallel.
Feel free to open supplementary Photometry dialog boxes if you wish to extend this parallel processing capability to a third, fourth, or any additional set of science images.
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