markall (Aug2004) | rjtools | markall (Aug2004) |
After displaying the image (if the image is already displayed and 'redispl = no' this step is omitted), a cursor cross or circle will appear in the display (the cursor shape may depend on the application used to display images, e.g. 'ximtool', 'saoimage' or 'ds9'), signaling that the task is ready to receive input and prompts for all of the of the specified object/defect types to be interactively marked, each in turn. For example, if all of the object types have been selected, then the user is prompted to first mark all galaxies, then mark all stars, subsequently followed by all cosmic ray hits, and finally to mark all defects.
To define an arbitrary circle enclosing an object or defect, the user should point at the center of that object/defect and hit the 'v' key once, then point at a point on the circumference of the circle and hit 'v' a second time.
When many objects/defects are to be marked that can be enclosed by a circle of the same radius, one may instead define a default radius by hitting the colon (':') key once and, when the cursor prompt has reappeared in the IRAF xgterm, typing 'rad' followed by a space (' ') and the size of that default radius in pixels, e.g., ':rad 7'. Note, that it is important not to type "rad" before the prompt has reappeared, or the format of the output file may get corrupted. After entering the default radius, hitting return, and waiting for the cursor cross to reappear in the image display window, one can mark objects by pointing at their center and hitting 'c' once.
To mark objects/defects with an arbitrary rectangular region that encloses them, move the cursor to one of the corners of that region and hit the 'b' key once. Then move the cursor to the diagonally opposite corner and hit 'b' again.
When all objects/defects of the current type have been marked, hit 'q' and the task continues to the next type, if any. If all specified types of objects/defects have been marked, hitting 'q' will exit the task. Each type is marked on the display with differently colored regions: galaxies are marked in white, stars in red, pixels affected by cosmic ray hits in blue and defects/blemishes in yellow, and for each type a seperate regions file is output. The names of those regions files are constructed by appending ".pos.gal", ".pos.star", .pos.cosmic", or ".pos.del" to the root of the input image name.
If 'append=yes', one may append to existing regions files (if for example some objects/defects were missed after a first pass), otherwise the task will rename and save the existing files by appending a tilde '~' to their names.
rj> markall N3795B.fits[128:384,128:384] MARKALL: IRAF2.12.2 raj@hasnap Apr 22 22:16:48 2004 image = N3795B.fits[128:384,128:384] [257 x 257] Wait for the cursor cross to appear in the image display area, then mark all galaxies in the image. The following key-strokes are recog- nized: hit v twice -- circle (center+circumference) hit b twice -- rectangle (diagonally oposite corners) hit :rad radlen -- set radius of circle to radlen hit c -- circle with radius radlen (center) hit q -- quit NB: after hitting a colon, don't type \"rad\" to quickly. ... (mark all galaxies) ... Wait for the cursor cross to appear in the image display area, then mark all stars in the image. ... (mark all stars) ... Wait for the cursor cross to appear in the image display area, then mark all pixels affected by cosmic ray hits in the image. ... (mark all cosmics) ... Wait for the cursor cross to appear in the image display area, then mark all CCD defects and other blemishes in the image. ... (mark all defects) ...MARKALL: Finished.