Get your science in Shape
Render Module
Properties Panel:
Selected Window
Properties Panel: Selected Window
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The Render Module can have several render windows, which can be of type Image or P-V (Position-Velocity). Each of them may have different parameters, which are listed and managed in the "Selected Window" panel. The selection is done by right-clicking on a window. The selected window is then highlighted by a white boarder that is thicker than that of the others. The parameter panel changes automatically when you change the selected window.
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While there are some parameters that they have in common, the Image and the P-V windows have different sets of parameters. First we will discuss those of the Image window. Then we describe the additional parameters that correspond to the P-V window. The common parameters will not be repeated here.
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2D Image
Render: This flag determines whether this window is to be update after the next rendering process (on) or shall keep the previously rendered image (off). By default this flag is set to on.
If you have several image windows, it may be desirable to keep the previous result to compare with another window that is updated.
Master: If you use the data of an image in an other module, this can be done only for one of the image windows. The one that is used is the one with the Master flag on. When you change the flag of one window from off to on, then the window that previously had the Master flag on is automatically switched off.
Window Parameters:
Under the Master flag there is a group of four icons that invoke utility commands. The first one copies the window parameters into a buffer. If you have additional windows of the same type and want them to have the same initial parameters, then you use the second button to paste the buffered window parameters to another window (after selecting it by clicking on the window).
The third button saves the image of a window to file. Note that you need to provide the filename with the appropriate extension, e.g. .png. Shape selects the format of the image file according to the file extension that you provide.
The fourth icon lets you print the image of the window to a printer or save it as a file in PDF format. It basically embeds the image in a PDF-file. Note that the image annotations, such as coordinates are not saved in a separate scalable font, but are incorporated in the pixelized image.
Seeing: The combination of image degradation from atmospheric seeing and instrument resolution is simulated by a convolution of the image with a Gaussian kernel with a full-width half-maximum (FWHM) of this value. It uses the same units as those chosen in the Units Panel of the Render Module.
Slits: The slits drop-down list contains the slits that correspond to the P-V windows. In this list they can be switched off from this image window by unchecking them.
If the "Move Slit" button above the image window is on, you can click on a slit and move it by pressing the left-mouse button and dragging it horizontally. After clicking on a slit and then moving the mouse-wheel, the slit-width can be changed interactively.
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The color of a slit helps to identify the P-V window to which it corresponds. The P-V window has a thick vertical line of the same color.
Background Image:
This section of the Selected Image Window Panel controls the file, positioning and appearance of the reference image that is loaded into the background layer of the image display.
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Image: From this drop-down list the current background image is selected. By default it is the "Observed" image, which can be loaded from file.
Initially there is one other option called "None", which displays no image. However, when the None option is selected, the currently rendered image can be added to the list as a reference to be compared to later renders. It is often useful to compare renders from changed parameters with the previous version to see the effect of the parameter change. When selected, a button appears that allows one to delete such an image from the list when no longer needed.
Transparency: In order to interactively compare the rendered image with the background image, the transparency of the rendered image is changed using the slider. If the slider is moved to the right, the transparency increases and the background image gradually appears. To help identifying whether the rendered or the background image is visible, the background image is marked with a red square in the top-left corner.
Filename: The file path and name of the Observed background image. Click on the icon on the right of the filename field to select a file from disk.
x0, x1, y0, y1: The coordinates of the bottom-left (x0,y0) and top-right (x1,y1) corners of the observed image. If all values are left at 0 (default), then the image fill the current image range. Setting custom values allows a precise placement of the image.
Modifiers: The appearance and positioning of the Observed image can be adjusted using various operators, called modifiers. They can be selected from the "Available Modifiers" drop-down list. It is then added to the Modifier list that is applied to the image. Each of them has it´s own set of parameters, which in most cases are self-explanatory.
PV Window
The first few parameters of a P-V Window are the same as those of an Image Window. Please refer to that section above for an explanation.
Slit color: In many projects data for several slit positions are available. To more easily relate them with the slit marking in the image window and the parameter panel, you can set individual slit colors. Default colors are assigned randomly.
Slit X, Slit Y: The horizontal and vertical position of the slit, respectively. It can be set numerically in this field or interactively with the mouse cursor by dragging the slit on the Image Window. Make sure to activate the "Move Slit" icon above the Image Window first to enable the interactive functionality. By default the slit can only be moved horizontally. To interactively move it vertically press "y" at the same time as you drag it up or down.
Slit width, Slit height: The slit width can be changed interactively after activating the "Move slit" button above the Image Window using the mouse wheel. By default the width is changed. If at the same time you press the "y" key, the height of the slit is changed interactively. Naturally, you can also change the values manually in the number fields.
Velocity: The reference velocity for the spectroscopy is set in the "Spectrum" section of the Render Module. In the scale of the P-V window the zero-velocity for the graph can, however, be shifted by the value of this parameter. I maintains the same total range as before.
Range: The total width of the P-V Window in units of velocity.
Resolution: The P-V image is convolved with a Gaussian kernel of this full-width half-maximum (FWHM) in horizontal direction in units of velocity.
Background Image: This section is similar to that for the Image Window as described above. Please refer to that section.