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Hi all,I am working on photometry of an Abell cluster with some 500 galaxies in the field. Galaxies have to be marked manually. I am doing this via center task, interactively. I've enabled the the neccessary options to mark the centers in ds9, and the dots are drawn.However, it takes some 15 seconds for each dot to appear. This is obviously very time consuming and actually drives me mad.When I turn off the marking options off, the centers are calculated instantaneously (coordinates are also written to file - no problem). I would like to keep displaying the dots, because otherwise I often get lost in the dense field of glaxies and mark some galaxies twice, and some never at all (this requires manual editing of the ctr files later...very time consuming).So my question is: is there any way to speed things up when center marks are displayed in interactive centering mode?Machine is an notebook running Ubuntu Linux (debian based), 1.7GHz P4 Mobile with 512MB RAM, images are 2048*4096.Thank you very much!

Someone who actually knows something will have to answer the specific question, but let me note that there might be two alternative ways around this issue for you:a) Mark the approximate centers using tvmark:
unlearn tvmark
tvmark 1 xyfile interactive+
and just drive around the image display hitting "a" (for "add").
This gives you a file that contains the x and y coordinates of where
the cursor was when you hit a "a". Then, run center on this file. To
make sure everything worked to your satisfaction, display the image
again, and overmark the centered coordinates using tvmark again:
tvmark 1 xyfilecentered interactive-
where xyfilecentered is the output of center.b) I'm surprised that you can't take advantage of "daofind" to find the
approximate centers of most of the galaxies. You would have to specify a
very large fwhm, and play around with sigma, round, and sharp, to see what
worked pretty well. Whatever it missed, you could then add by hand.

Phil has some good tips on how to alternately use the task, see also the help page examples for using the CONTOUR plot instead of the display.That said, I wasn't able to reproduce your problem on an Ubuntu (or any other) setup here, and I can't imagine what would be causing the delay. Two ideas come to mind however: From the terminal window define a DEBUG_IIS environment variable before starting ds9, e.g.% setenv DEBUG_IIS 2
% ds9Then login to iraf in a different window. When you display or read the cursor you should see the IIS protocol messages being exchanged which will include the redraw of the pixels to make the mark and the cursor read request. If those requests come almost instantaneously the problem is on the DS9 side and you should be sure you're using the latest version. If there is a delay and the requests come 15sec later when the mark is drawn let me know.The second idea is to simply use the markers in DS9 directly as a workaround, e.g. hit the SpaceBar for the CENTER input and then click the left mouse button to make a mark on the screen. The circle size/shape can be adjusted using the Edit->Preferences->Region menu panel. Hope this helps.Cheers,
-Mike

Fitz and Massey, thanks for your help! I'll try the workarounds and try to figure out what is causing the delay. Meanwhile, I finished my tasks using a workaround method similar to one fitz suggestetd... I drew a rectangle encompassing a smaller part of the image and marked galaxies inside. This way I didn't loose track of what I marked and what I didn't mark.