Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.astro.louisville.edu/software/sbig/archive/xmccd-4.1/xmccd-4.1e/docs/ds9/ds9_user.pdf Äàòà èçìåíåíèÿ: Tue May 31 02:25:13 2011 Äàòà èíäåêñèðîâàíèÿ: Thu Feb 27 22:29:57 2014 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï ï

Table of Contents
DS9 Users Manual . . . . . . . . . . . . . . . . . . 1

SAOImage DS9 Users Manual

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Introduction to the ds9 Interface - DS9 . Introduction to the ds9 Interface . . . Synopsis . . . . . . . . Contents . . . . . . . . The ds9 Interface . . . . . . Figure 1: The ds9 GUI . . . . Figure 2: The ds9 GUI, vertical layout 1. Menu bar . . . . . . Figure 3: Menu bar . . . . . Figure 4: Tearing off a Menu . . 2. Information panel . . . . Figure 5: Information panel . . . 3. Panner . . . . . . . Figure 6: Panner . . . . . 4. Magnifier . . . . . . Figure 7: Magnifier . . . . . 5. Buttons . . . . . . . Figure 8: Buttons . . . . . 6. Display frame . . . . . Figure 9: Tiled frame display . . 7. Colorbar . . . . . . Figure 10: Colorbar . . . . . Setting and Saving View Preferences . Figure 11: Preferences dialog box . History . . . . . . . . Binning and Filtering FITS Event Files - DS9 Binning and Filtering FITS Event Files . Synopsis . . . . . . . . Contents . . . . . . . . Getting Started . . . . . . Figure 1: Data loaded with default buffer Figure 2: The Bin menu . . . . Buffer Size . . . . . . . Figure 3: Buffer size set to 128x128 . Figure 4: Buffer size set to 4096x4096 Binning Basics . . . . . . Changing the binning factor . . .

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Figure 5: Data binned by a factor of 4 . . . . . . Binning different columns . . . . . . . . Figure 6: The Binning Parameter dialog . . . . . Figure 7: Image binned in detector coordinates . . . . Data Cubes: Binning in three dimensions . . . . . Figure 8: Binning Parameter dialog for a data cube . . . Figure 9: Data Cube dialog box . . . . . . . Figure 10: Viewing a data cube . . . . . . . Filtering Data . . . . . . . . . . . . Figure 11: Filtering data . . . . . . . . . History . . . . . . . . . . . . . Contours - DS9 . . . . . . . . . . . . Contours . . . . . . . . . . . . . Synopsis . . . . . . . . . . . . . Contents . . . . . . . . . . . . . Creating Contours on a Dataset . . . . . . . . Figure 1: Contour Parameters dialog box . . . . . Figure 2: X-ray data with contours . . . . . . Copying the Contours to Another Frame . . . . . . Figure 3: SAO-DSS Server dialog box . . . . . . Figure 4: X-ray and optical data with contours . . . . Saving the Contours . . . . . . . . . . Converting to Polygons and Saving . . . . . . . History . . . . . . . . . . . . . Create a True Color Image in an RGB frame - DS9 . . . . Create a True Color Image in an RGB frame . . . . . Synopsis . . . . . . . . . . . . . Contents . . . . . . . . . . . . . Creating an RGB Frame . . . . . . . . . A. From the command line . . . . . . . . B. From the ds9 GUI . . . . . . . . . Figure 1: RGB window . . . . . . . . . Figure 2: Lock menu in the RGB window . . . . . Figure 3: RGB frame with three files loaded . . . . Apply Energy Filters . . . . . . . . . . Figure 4: Energy-filtered RGB data . . . . . . Smoothing the Data (optional) . . . . . . . . Figure 5: Data smoothed with a Gaussian of radius three . . Adjusting the Scale Parameters . . . . . . . . Figure 6: The adjusted pixel distribution for scaling . . . Adding a Coordinate Grid . . . . . . . . . Figure 7: Coordinate Grid parameters dialog box . . . Figure 8: Final three-color image with coordinate grid overlaid Saving the Output . . . . . . . . . . . History . . . . . . . . . . . . .

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Scripting ds9 - DS9 . . . . . . . . . . . Scripting ds9 . . . . . . . . . . . . Synopsis . . . . . . . . . . . . . Contents . . . . . . . . . . . . . Command-line Scripting . . . . . . . . . Figure 1: Command line: x-ray data with contours . . . Figure 2: Command line: x-ray and optical data with contours XPA Scripting . . . . . . . . . . . Figure 3: XPA: x-ray data with contours . . . . . Figure 4: XPA: x-ray and optical data with contours . . SAMP: Simple Application Messaging Protocol . . . . History . . . . . . . . . . . . . Catalogs - DS9 . . . . . . . . . . . . Catalogs . . . . . . . . . . . . . Synopsis . . . . . . . . . . . . . Contents . . . . . . . . . . . . . Displaying a Catalog . . . . . . . . . . Figure 1: 2MASS Sources for the Antennae Galaxies . . Figure 2: Catalog Tool of 2MASS Sources . . . . . Selecting Sources with the Cursor . . . . . . . Displaying Multiple Catalogs . . . . . . . . Figure 3: CSC and 2MASS Sources for the Antennae Galaxies Clearing Catalog Sources . . . . . . . . . Sorting and Filtering . . . . . . . . . . Figure 4: 2MASS Sources Sorted by Decreasing Jmag . . Figure 5: Filtering 2MASS Sources: Jmag<14 . . . . Figure 6: Filtering 2MASS Sources: Jmag<14 or Jmag>16.5 . Specifying Symbols with Conditional Expressions . . . Figure 7: Symbol Editing: Jmag<14 Rule . . . . . Figure 8: Symbol Editing: Jmag<14 Sources Displayed . . Figure 9: Symbol Editing: Jmag>16.5 Sources Added . . Figure 10: Symbol Editing: Rule to Add a Label . . . Figure 11: Symbol Editing: Jmag Labels Displayed . . . Saving the Sources: Catalog Files and Region Files . . . Citing a Catalog in Publication . . . . . . . . History . . . . . . . . . . . . .

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SAOImage DS9 Users Manual

The DS9 Users Manual leads the user step-by-step through many features of ds9, such as data binning and contours. For an in-depth description of all of ds9's capabilities, refer to the Reference Manual Introduction to the ds9 Interface Binning and Filtering FITS Event Files Contours Create a True Color Image in an RGB frame Scripting ds9 Catalogs If there are topics that you would like to see covered in the Users Manual, please email: saord @ cfa.harvard.edu.

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Introduction to the ds9 Interface
Return to the DS9 Users Manual

Synopsis
This thread provides an overview of the key components of the ds9 graphical user interface (GUI). If you encounter any problems, please email saordá @á cfa.harvard.edu.

Contents
The ds9 Interface 1. Menu bar 2. Information panel 3. Panner 4. Magnifier 5. Buttons 6. Display frame 7. Colorbar Setting and Saving View Preferences History Images Figure 1: The ds9 GUI Figure 2: The ds9 GUI, vertical layout Figure 3: Menu bar Figure 4: Tearing off a Menu Figure 5: Information panel Figure 6: Panner Figure 7: Magnifier Figure 8: Buttons Figure 9: Tiled frame display Figure 10: Colorbar Figure 11: Preferences dialog box

The ds9 Interface
This thread uses Chandra data from an observation of the Trapezium Cluster (ObsID 1522). The default ds9 GUI is shown in Figure 1. The main components are numbered:

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1. 2. 3. 4. 5. 6. 7.

Menu bar Information panel Panner Magnifier Buttons Display frame Colorbar

Figure 1: The ds9 GUI

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The default setup is a "horizontal layout", with the information panel, panner, magnifier, and buttons displayed horizontally across the window. This may be changed to "vertical layout" in the View menu (Figure 2).

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Figure 2: The ds9 GUI, vertical layout

Note that the colorbar remained horizontal at the bottom of the display frame. This may be changed with the "vertical colorbar" option in the "View" menu.

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1. Menu bar
The menu bar provides access to all of ds9's capabilities. For a complete description of each menu, refer to the Menu bar section of the Reference Manual.

Figure 3: Menu bar

All ds9 menus can be "torn off" to be a separate window from the main GUI. To tear off a menu, select the dashed line, which is the first item of each menu (shown in Figure 4). The menu will become its own window.

Figure 4: Tearing off a Menu

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2. Information panel
The information panel displays information about the data file and the values at the cursor position. In Figure 5, the object name has been loaded from the header of the data file. The image value and position (in WCS, physical, and image coordinates) are updated in real time as the cursor is moved. The fields of the information panel can be customized from the "View" menu. Any of the default entries can be removed, and additional fields can be added (e.g. detector coordinates, min/max data values).

Figure 5: Information panel

3. Panner
The panner allows the user to view areas of the frame which are outside of the current field of view. Although the display frame is filled by the data, the panner indicates that more of the image is available. Clicking and dragging the viewing bounding box in the panner - shown in blue in Figure 6 - will display a different portion of the image. The panner also contains axes to indicate the directions of North and East and the directions of the physical (x,y) data axes.

Figure 6: Panner

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4. Magnifier
The magnifier displays a magnified view of the current cursor location. The magnifier cursor - the small square in the center of Figure 7 - outlines the size and orientation of one pixel, taking into account the current frame zoom and orientation.

Figure 7: Magnifier

5. Buttons
The button bar duplicates many of the options available from the menu bar. The buttons provide quick access to change the most frequently-used ds9 actions (e.g. changing the scale and color bar, blinking and tiling frames). When a category is chosen from the top row, the options within that category are displayed in the bottom row of buttons. In Figure 8, the color category is chosen and the bottom row shows the ten most-used colormap options (additional colormaps are available from the "Color" menu).

Figure 8: Buttons

6. Display frame
The display frame is the area of ds9 where the FITS image is shown. In Figure 1, a single frame is shown. Multiple frames can be opened in ds9 at the same time. In Figure 9, nine frames have been opened and set to "tile" display from the "frame" button. The current frame is indicated by a blue outline around it (second row, center frame). How the frames are tiled is set in the "Frame Á Frame Parameters Á Tile" menu; the default is to tile the frames in a grid.

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Figure 9: Tiled frame display

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If the display is set back to "single", then the current frame fills the display area. The other frames can be accessed via the "previous" and "next" options in the buttons bar (or from the "Frame" menu). The "blink" option may also be used with multiple frames. When blink is turned on, ds9 cycles through all the available frames. The blink interval is set in the "Frame Á Frame Parameters Á Blink Interval" menu.

7. Colorbar
The colorbar displays the colormap, bias, and contrast settings. The colormap correlates the colors used in the image with the pixel values in the data. To change the colormap, use the "Color" menu or button. The contrast and bias can be adjusted by right-clicking and dragging on the ds9 display. The "Color Á Colormap Parameters" dialog box can also be used to change contrast and bias.

Figure 10: Colorbar

Setting and Saving View Preferences
All of the view options described in this thread can be set and saved as a preference. Open the "Preferences" dialog box from the "Edit" menu and select the "View" tab, shown in Figure 11.

Figure 11: Preferences dialog box

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The "Default" menus are used to set the defaults of the "View" menu and buttons. For instance, uncheck the "Panner" item under "Menu" and the panner won't be displayed when ds9 is launched. (Note that some options require ds9 to be restarted before they take effect.) After setting the desired preferences, select "Save". User preferences are stored in .ds9.prf. At startup, ds9 looks for the preferences file in the following directory order: ./, $HOME, /usr/local/lib, /opt/local/lib.

History
06á Julá 2009 Original version

Return to the DS9 Users Manual

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Binning and Filtering FITS Event Files
Return to the DS9 Users Manual

Synopsis
When an x-ray event file is loaded, ds9 makes a virtual image for display by binning on one or more axes. This threads describes how to adjust the binning and buffer sizes. Interactive data filtering is described, as well as binning in three dimensions. Note that the terms "binning" and "blocking" are used interchangeably in this thread. They both refer to combining pixels in an image. If you encounter any problems, please email saordá @á cfa.harvard.edu.

Contents
Getting Started Buffer Size Binning Basics Changing the binning factor Binning different columns Data Cubes: Binning in three dimensions Filtering Data History Images Figure 1: Data loaded with default buffer and bin size Figure 2: The Bin menu Figure 3: Buffer size set to 128x128 Figure 4: Buffer size set to 4096x4096 Figure 5: Data binned by a factor of 4 Figure 6: The Binning Parameter dialog Figure 7: Image binned in detector coordinates Figure 8: Binning Parameter dialog for a data cube Figure 9: Data Cube dialog box Figure 10: Viewing a data cube Figure 11: Filtering data

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Getting Started
This thread begins with Chandra data from an observation of the Antennae Galaxies (NGC 4038/NGC 4039, ObsID 315). Open the file in ds9:
unix% ds9 acisf00315N002_evt2.fits &

A small section of the data is visible when the file is loaded, as shown in Figure 1. The target of the observation is partially visible in the display frame.

Figure 1: Data loaded with default buffer and bin size

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By default, the buffer size is set to 1024x1024 and the binning factor is set to 1. These values will be adjusted in the following sections to illustrate how to make more of the data visible. The "Bin" menu, shown in Figure 2, will be used to change the setting in the following examples. From top to bottom, this menu contains the bin function setting, blocking factor, buffer size options, and access to the binning parameters dialog box.

Figure 2: The Bin menu

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Buffer Size
The buffer size determines the size of the image generated by ds9. By default, a full-resolution 1024x1024 image of the data is created. If your input data file has larger dimensions, it is clipped to 1024x1024 in ds9. The buffer settings range from 128x128 to 8192x1892. Setting the buffer to the smallest size, 128x128, illustrates how it works. The data was centered on the sources in ds9 before the buffer size was changed, creating Figure 3.

Figure 3: Buffer size set to 128x128

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Setting the buffer to a large size, e.g. 4096x4096, produces Figure 4. The display frame is filled by the data, and the panner in the upper right indicates that more of the image is available. Clicking and dragging the viewing bounding box in the panner will display a different portion of the image.

Figure 4: Buffer size set to 4096x4096

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Binning Basics
Changing the binning factor
While increasing the buffer size loads more of the file into ds9, binning the data makes more of it visible in the frame. Binning combines the specified number of pixels into one new pixel; the new pixel has a value equal to the sum of the original pixels. (Note that if the bin method is changed to "average", the pixel values are averaged instead of summed.) The binning can changed from the "Bin" menu or from the "Bin" item in the button bar. It's also possible to step through different binning values with the -/+ buttons or the "Block In"/"Block Out" menu items. In Figure 5, the buffer size is set to 1024x1024, but the block factor has been set to 4. A larger section of the data is visible in the frame.

Figure 5: Data binned by a factor of 4

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Binning different columns
ds9 has the ability to display any of the other columns stored in the event file, although it is generally only meaningful to use the spatial vector columns. Begin by opening the "Bin Á Binning Parameters" dialog box, shown in Figure 6. The "Bin Columns" menus are used to select the columns to be binned. To create an image in detector coordinates, set the first to "detx" and the second to "dety"; the block is set to "2" for both. The "or center of data" box is checked so that the center of the data is recalculated for the new columns.

Figure 6: The Binning Parameter dialog

Click "Apply" and the ds9 frame is updated, as shown in Figure 7.

Figure 7: Image binned in detector coordinates

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Alternatively, one can display an event file in specific coordinates when starting ds9 from the command line:
unix% ds9 "acisf00315N002_evt2.fits[bin=detx,dety]" &

Data Cubes: Binning in three dimensions
It is possible to add a third column to the binning, creating a 3-dimensional image also known as a "data cube". In this example, an (x,y,time) data cube is created of a Chandra observation of Jupiter (ObsID 1463). A cube may be created from any three columns that make sense in the analysis. For instance, you may want to create a PHA or energy axis to see how the spectral characteristics of a source change over time. The data file is loaded into a new frame in ds9 and the "Bin Á Binning Parameters" dialog box is opened again. The "time" column of the file is selected from the "Bin 3rd Column" menu. The limits of the data in that column are filled in automatically. The "depth" field determines how many intervals the column is divided into; a depth of 25 is used. The completed parameter box is shown in Figure 8.

Figure 8: Binning Parameter dialog for a data cube

After clicking "Apply", two things happen: the "Data Cube" dialog box (Figure 9) is launched and the frame is updated to show only the (x,y) image of the first time slice (Figure 10). (If the data cube dialog box doesn't launch, open it from the "Frame" menu.)

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Figure 9: Data Cube dialog box

When "Play" is chosen, ds9 cycles through the bins of the time axis, essentially creating a movie of the (x,y) position of the object over time. The speed of the frame changes is controlled from the "Interval" menu of the dialog box. Any of the 25 intervals may be selected with the slider bar.

Figure 10: Viewing a data cube

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The data cube can be saved as an MPEG movie from the "File Á Save Image..." menu. Select "MPEG-1 (Movie)" and click "OK"; after setting the filename, choose an MPEG Quality Factor. The Jupiter data was saved at a quality factor of 15: jupiter.mpg.

Filtering Data
The "Bin Filter" field in the "Binning Parameters" dialog box is used to apply filters to the data. A filter can be applied to any of the columns present in the input file. A colon is used to indicate a range of values. Filters can also use < (less than) or > (greater than). For instance, to include only the hard-band photons (2500-8000 eV):
energy=2500:8000

Clicking "Apply" updates the ds9 display and keeps the dialog open for adjusting the filters. Multiple filters may be specified, separated by commas:
energy=2500:8000, ccd_id=7

The resulting image is shown in Figure 11.

Figure 11: Filtering data

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The filtered dataset can be saved as a FITS file for use in data analysis from the "File Á Save Frame as Fits..." menu.

History
26á Juná 2009 Original version

Return to the DS9 Users Manual

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Contours
Return to the DS9 Users Manual

Synopsis
Contours are curves along which the pixels have a constant value. ds9 can create and display contours as an overlay on a data image. The contours can be copied between frames in the current session or saved to file for future use with ds9. If you encounter any problems, please email saordá @á cfa.harvard.edu.

Contents
Creating Contours on a Dataset Copying the Contours to Another Frame Saving the Contours Converting to Polygons and Saving History Images Figure 1: Contour Parameters dialog box Figure 2: X-ray data with contours Figure 3: SAO-DSS Server dialog box Figure 4: X-ray and optical data with contours

Creating Contours on a Dataset
This thread uses Chandra data from an observation of the galaxy cluster Abell 2142 (ObsID 5005). After loading the data into ds9 and setting the desired scale, click on the "Contours" item in the "Analysis" menu to turn on contour display. Open the "Contour Parameters" window from "Analysis Á Contours Parameters". There are two sliding scales which are used to set the number and smoothness of the contours and fields for setting the range of values to use.

Figure 1: Contour Parameters dialog box

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Typically, you will want to generate between 1 and 10 contours; larger numbers will take longer to generate and display. A smoothness level of 1 will evaluate the contour at each image pixel, while a level of 2 will evaluate the contour at every other pixel, and so on. A larger smoothing will generate contours more quickly, but less detail will be available. By default, the range of the data scale is filled in as the limits. Under the "Method" menu, there are two choices: 1. block (the default) - blocks down the image by the smoothness factor before contours are calculated. The larger the smoothness, the faster the result. 2. smooth - smooths the image before calculating contours. The larger the smoothness, the slower the result. In this example, the number of levels is set to 6 and the smoothing is set to 5. The contours will be generated over the limit 1 to 100. The default method (block) is used. After clicking the "Generate" button, the list of contours is calculated and displayed in the "Levels" portion of the window. Click "Apply" and the ds9 display is updated with the new contour levels, as shown in Figure 2.

Figure 2: X-ray data with contours

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The contour parameters can be adjusted until the desired result is achieved. Be sure to click "Generate" whenever an adjustment is made so that the levels are recalculated.

Copying the Contours to Another Frame
In this section, we take the X-ray contours just generated and display them on an optional image from the Digital Sky Survey (DSS). From the "Analysis Á Image Servers" menu, select one of the DSS server options (e.g. "SAO-DSS"). The server dialog box allows you to retrieve an optical image of the field of your observation and load it into a new frame. The default retrieval image size and (RA,Dec) is equal to the size and center of the field currently displayed. Here the width and height have been set to 40, but the (RA,Dec) determined by ds9 are used.

Figure 3: SAO-DSS Server dialog box

Click on "Retrieve" and the data is loaded into a new ds9 frame. To copy the x-ray contours: 1. Select the frame with the X-ray data in it. 2. Use "Frame Á Match Frames Á WCS" to align the two images. 3. To copy the contours, open the "Contour Parameters" dialog again and select "Copy Contours" from the "File" menu. Leave the window open, as it is needed in a future step. 4. Select the frame with the optical data in it. 5. Using the "File" menu of the "Contour Parameters" dialog, select "Paste Contours".

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6. Adjust the parameters (if desired) in the small dialog box that is displayed, then click "OK". The optical image now has the x-ray contours overlaid. Since the WCS is the same, correlation between x-ray and optical features may be seen.

Figure 4: X-ray and optical data with contours

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To delete contours which have been pasted into a frame, select "Clear" from the "File" menu of the "Contour Parameters" dialog.

Saving the Contours
To save the contours to a text file, choose "Save Contours" from the "File" menu of the "Contour Parameters" dialog. The contours are saved in a text file which can be loaded back into ds9 with the "Load Contours" menu item. The contours generated in this thread have been saved as ds9.con.

Converting to Polygons and Saving
The contours can be converted to ds9 polygon regions for use in filtering data. Converting to polygons also allows you to select and/or delete specific contours. Note that the contours cannot be saved in ds9 format after converting. If you wish to save the contours, do so before continuing. To convert the contours, select "Convert to Polygons" from the "File" menu of the "Contour Parameters" dialog. The contours are now defined as ds9 polygons, e.g.
polygon(3535.2112,4184.5,3540.5,4179.1154,3548.5,4176.8219,3555.9012,4184.5,3548.5,4191.9558,3540.5,4190.3926)

The polygon-shaped contours can be saved as a ds9 region file from the "Region Save Á Regions" menu. The region file for these contours has been saved as a2142.reg.

History
24á Juná 2009 Original version

Return to the DS9 Users Manual

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Create a True Color Image in an RGB frame
Return to the DS9 Users Manual

Synopsis
Most astronomical images map color to intensity level, e.g. lighter tones may correspond to a brighter intensity level in a greyscale image. An alternative way of presenting data is via an image that correllates color and energy. ds9 has the capability to create an RGB image and interactively adjust many of its parameters to achieve optimal display results. If you encounter any problems, please email saordá @á cfa.harvard.edu.

Contents
Creating an RGB Frame A. From the command line B. From the ds9 GUI Apply Energy Filters Smoothing the Data (optional) Adjusting the Scale Parameters Adding a Coordinate Grid Saving the Output History Images Figure 1: RGB window Figure 2: Lock menu in the RGB window Figure 3: RGB frame with three files loaded Figure 4: Energy-filtered RGB data Figure 5: Data smoothed with a Gaussian of radius three Figure 6: The adjusted pixel distribution for scaling Figure 7: Coordinate Grid parameters dialog box Figure 8: Final three-color image with coordinate grid overlaid

Creating an RGB Frame
To use the three-color capabilities of ds9, the data must be loaded into a special RGB frame. This frame will contain all three files, stacked together in separate layers.

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This thread uses Chandra data from an observation of Cas A (ObsID 198); the level=2 event file is named "casa.fits". The same file is loaded into each layer of the RGB frame; different energy filters will be applied to the layers in a later step. There are two options for creating the RGB frame:

A. From the command line
The command-line syntax can be used to create the RGB frame and load the three files into the red, green, and blue layers:
unix% ds9 -rgb -red casa.fits \ -green casa.fits \ -blue casa.fits &

ds9 will open with the three files in one frame. The RGB window (Figure 1) should open as well. If it doesn't, open it from the "Frame Á RGB..." menu.

B. From the ds9 GUI
To load the files from the ds9 GUI: 1. Launch ds9 2. Choose "New Frame RGB" from the "Frame" menu. When the new frame is created, the RGB window (Figure 1) should open as well. If it doesn't, open it from the "Frame Á RGB..." menu. 3. Make sure the "Red" band is selected in the "Current" column of the RGB window, then choose "File Á Open..." in the main ds9 window and select the red file. 4. Change