RegionOfInterest Window Introduction The main ROI window and many of the sub-roi pop-ups update automatically as the images in the main window are manipulated. The ROI window allows a subsection of the work area to be examined in greater detail. The ROI Widget is activated in one of two ways: 1. a region is dragged out in the main display by the left mouse button 2. a center pixel is selected with the left mouse button and the ROI is created as a box of roi_box size about the center pixel. The ROI region that has been selected is highlighted in the designated ROI color in the main display. Cursor functions for the ROI are defined by the Mouse Mode Selection. The user may refresh the display at any time with the Redisplay button. The ROIMask may be turned ON and OFF with the ROIMaskOn button. The right ascension and declination of the cursor position is displayed immediately above the image when valid WCS are present for the reference image. The x and y positions as well and pixel value and the ROI zoom factor are displayed at the bottom of the image. Menus File Menu Load submenu ROI Mask Load a fits or hdf mask file where good is denoted by the mask good value (idp3_preferences). The ROI mask is overlaid upon the ROI display and should not be confused with the individual image masks associated with the main display. Region of Disinterest Load a region of disinterest mask created with the annotate widget. Print submenu ROI Pops up print widget for selecting filename and format for the output file. Save submenu ROI Pops up save widget for saving the ROI. The user may select to save the ROI to memory and/or file on disk. Data format for files written to disk is FITS. The ROI may be saved at its original coordinates in the main image where surrounding pixels are set to the fill value or the ROI may be saved with its data origin at [0,0]. ROI Mask Pops up widget for saving mask. User specifies filename. Region of Disinterest Pops up widget for saving region of disinterest. User specifies the filename. Centroid Solutions Pops up widget for saving the centroid solutions that have been calculated in the Radial Profile Widget. User specifies the file name. Close Closes the ROI and all subwidgets. Adjust Menu Adjust Display Allows the user to see and modify the display minimum and maximum for both the main and ROI windows. If flux is conserved the minimum and maximum for the main display are divided by the square of the zoom factor to set the limits for the ROI display. Adjust Coordinates Allows the user to adjust the coordinates of the ROI by changing the start, stop, center, or length for the x and y axes. The user may also use the centroid solution to center the ROI. Zoom Menu 1 - 64 Powers of 2 zoom steps (1-64) for the ROI window. When pressed, window resizes itself and redisplays the data at the new zoom factor. Align Menu Centroid by Reference WCS If each image that is "ON" has a valid World Coordinate System each may be centroided relative to the reference image using the WCS for a first guess of the centroid center. Before using this routine a centroid must be fit to the desired object in the reference image to determine its right ascension and declination of that object. The Radial Profile Widget must be also be active. The reference CD Matrix and the CRVALs for each image are used to determine the first guess of the centroid center. The advantage of this method (as opposed to Aligning by WCS and Realigning by Centroids - see below) is that the individual images are not shifted, hence no resampling errors, before the centroid solution that might bias the result. Centroid by Individual WCS If each image that is "ON" has a valid World Coordinate System each may be centroided relative to the reference image using the WCS for a first guess of the centroid center. Before using this routine a centroid must be fit to the desired object in the reference image to determine its right ascension and declination of that object. The Radial Profile Widget must be also be active. The CD Matrix and the CRVALs for each image are used to determine the first guess of the centroid center. The advantage of this method (as opposed to Aligning by WCS and Realigning by Centroids - see below) is that the individual images are not shifted, hence no resampling errors, before the centroid solution that might bias the result. Align by WCS All "ON" images may be aligned by comparing each WCS to that of the reference image. Align by Centroids All "ON" images may be aligned by comparing their centroid solutions to that of the reference image. Realign by Centroids When an object in all images that are "ON" is already aligned within 1.5 pixels (previously invoking Align by WCS or data taken with very small dithers) the alignment may be refined with Realign by Centroids. Align by X/Y Positions When each image is loaded the header is checked for target position keywords and a WCS. If the keywords, 'RA_TARG' or 'RA_REF' and 'DEC_TARG' or 'DEC_REF', are found as well as a WCS, the x/y position of the target in the image is computed. The user may align all of the "ON" images to the reference image based on these x/y positions. Undo Alignment X/Y offsets for all "ON" images are set to 0. to undo any alignment. Mask Menu Move ROI Mask Pops up a widget allowing the user to move the mask around in the ROI both horizontally and vertically. Invert ROI Mask Sets all bad pixels in the currently defined mask to good and vice versa. Remove ROI Mask Allows the user to discard the previously loaded mask. Masks are loaded and saved from the File Menu. Masks are turned ON and OFF via a button in the ROI Display. Define ROD Allows the user to create a "region of disinterest" with the Annotate Widget. Move ROD Pops up a widget allowing the user to flip the ROD vertically, horizontally, or the move the ROD around. Remove ROD Allows the user to discard the "region of disinterest". ROD's are loaded and saved from the File Menu. ROD's do not have the option to be turned off and on. Plot Menu Radial Profile submenu The Radial profile is initiated by dragging a circle with the mouse in the ROI. Most Radial Profile functions are contained within the Radial Profile Widget. For more detail about the Radial Profile see the help in its widget. Last Profile If a Radial Profile has previously been defined but the widget is not currently active, Last Profile will create a new Radial Profile Widget with the same parameters as the previously defined profile. When all images are deleted all subwidgets associated with the ROI are destroyed. Last Profile gives a means to recreate a radial profile in the same location as previously defined. Stack Profile Computes radial profiles for all "ON" images according to the radial profile that has been computed for the reference image. If values are assigned for the background offsets in the idp3_preferences file (rpbkgxoff, rpbkgyoff) radial profiles are also computed for a background region whose center is defined as profile xcenter + rpbkgxoff and ycenter + rpkgkyoff. The radial profile value, encircled energy value, and background encircled energy value at the radial profile radius are printed to file, 'stack_profile.txt' for each image. Finally, the mean and RMS of the above radial profile values, encircled energy values, and backround encircled energy values are printed to the file. Polygon submenu Undo Restores polygon to previous state. If the polygon was moved it will be returned to its original position, if a point was edited the point will be returned to its original position. Only the last adjustment to the polygon may be taken back to its previous state. Adjust Pops up a table widget of the the polygon vertices. Individual x or y values may be edited by double clicking on the point. Make Mask Masks the pixels inside of the polygon. If no mask is currently defined the user is prompted for the overall size of the mask. Otherwise, the masked region is added to the current mask. The mask is made in original pixels which may not align exactly with how the zoomed polygon region is drawn in the roi. Undo Mask The last polygon added to the mask is removed from the mask. Surface Plots submenu Surface A surface plot of the ROI data is shown Shad_Surf A shad-surf plot of the ROI data is shown Surf_Play The ROI data is passed to a complex surface visualization tool. Noise Profile Allows user to enter parameters for the noise profile statistics: x and y centers, beginning and ending annulus radii, annulus width, increment between annuli, and x and y pixel scales. Noise profile results may be saved and printed. For more details see help for Noise Profile in Noise Profile Widget. Collapse 1D Computes the row or column mean or median of data in the ROI. The result may be saved to disk and/or memory. See help for ROI 1D Collapse for more details. Histogram Displays a histogram of data in the roi. The number of bins in the histogram is determined by the value of hist_bins in the preferences file. Contour Map Pops up contour map of data in the ROI. Options include logarithmic spacing of levels, and to overlay contours on image. Contour map may be printed to postscript, tiff, pict, and jpeg formats. Cursor Toggle Toggle between standard cursor and a full width cross-hair cursor. *Cross Section is not in the plot menu because it is initiated by drawing a line in the ROI and all of its functions are contained within its widget. For help regarding the cross section see the help in the Cross Section Widget. Statstics Menu Spreadsheet Pops up a spreadsheet showing all the values of the pixels in the ROI. Automatic updates. Also, if the user clicks on a cell or pulls out a range of cells, a box is drawn around those pixels in the ROI. Statistics Pops up a widget showing the mean, variance, total, min, and max of the data in the ROI. The widget automatically updates as images are turned on or off. The results may be saved to a file named by the user in the widget. Aperture Photometry Computes photometry of a circular or square aperture defined by the center position and the target radius. Also background flux may be calculated for the annulus defined by the background inner and outer radii. Values are printed in the photometry window and may be saved to a text file. For more details about aperture photometry see help in Aperture Photometry Widget. Asymmetry Allows the user to measure the asymmetry and concentration parameter of galaxies and save results to an output file. For more details about galactic asymmetry see help in the Galactic Asymmetry Widget. Set Color Menu Set Color Allows user to set the desired color for each of the ROI graphics: radial profile circle, inner and outer noise profile circles, cross section lines, and polygons. Help Menu ROI Help Shows this file ROI Mouse Help Describes mouse modes supported in the ROI. Done Menu Done Exits the ROI widget. (Same as Close ROI in Plot Menu) Mouse Buttons Activities with the mouse buttons are controlled by the mouse mode selection made at the top of the roi widget. There is no distinction between which mouse button was used. See roi_mouse help for more details. An important note about cursor readback: Cursor readback is available in the ROI window. Cursor position is shown in main window pixels. It is very important to remember that FRACTIONAL POSITIONS ARE GIVEN TO THE RESOLUTION OF THE ROI ZOOM! That is, if the ROI zoom is 4, the cursor position is reported to the nearest 1/4 pixel. Therefore, positions of image features MAY BE REPORTED SLIGHTLY DIFFERENTLY AT DIFFERENT ROI ZOOM FACTORS! The user should experiment with this to convince himself or herself that he or she understands how this works before attempting to locate object positions to fractional pixels.