Place wavdetect sources on the image

First, we construct an ASCII ds9 region file from the wavdetect source list so the sources can be displayed superposed on the image. This involves converting the wavdetect source list FITS file into ASCII (using FTOOL fdump or CIAO dmlist), and editing it into a region file format; e.g., circle 3850 4129 6 where the last value is the pixel radius of the marker.
A C program marker based on FTOOLS written by J. Wolovitz makes these region files. It is currently set to make circles; the line " printf(dfp,"circle(%f,%f,%f)\n",x,y,scale);" in marker.c can be changed to make other marker shapes. Usage: where first parameter is the input source list file from wavdetect, the second parameter is the output region file, and the last parameter is the radius in pixels of the markers. See "marker -help" for more information.


Second, we display the image with the swvelet sources superposed: In the Region menu, Load regions, and click on Region_wav.reg. Colors, but not shape/size of the markers can be changed, and other annotations can be added.

It is sometimes helpful to display various characteristics of the wavdetect sources onto the image in ds9. Y. Maeda has two Perl scripts based on FTOOLS, mkcountplot.pl and mknumberplot.pl which respectively create region files displaying the source counts and source number from the wavdetect source list file. The line "system("ftabpar $list[$i] NET_COUNTS $j");" can be changed to plot other characteristics (such as SRC_SIGNIFICANCE) from the wavdetect source list. Usage:

From these displays, we can carefully examine the performance of wavdetect for sensitivity, false and missing sources. As problems most usually arise near the threshold, it is useful to display small portions of the image at full resolution (Block=1, Zoom=4) with the color palette set to distinguish 0,1,2 photon pixels. Use the middle mouse button to navigate across the image in an organized manner.

Several options are available for producing contour maps of ACIS image upon which source positions can be superposed. These include the IDL intrinsic routine IMAGE_CON, and routines imcont.pro and imcont2.pro written by H. Ebeling (Hawaii).