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Hot Pixel Map Creation

All steps needed to create a hotpixel map for guider cameras at MAGELLANS.

  1. Make sure the dome is as dark as possible.
  2. The TV camera, GCAM# (#=1 or 2), must be turned on at least one hour before starting dark frames.
  3. Set tec 2 and sh 1 to cool down the camera as well as allowing image trasference.
  4. Define tf 10 and avf 30.
  5. Send the images to ALPACA or VICUNA depending on telescope.
  6. These images will appear into directory /home/mag#op/public_html/images/.
  7. Type command ls - ltr to see last individual imageName from the list which should correspond to the one sent from the camera.
  8. Copy the last image into a working directory that must be created previously by the user.
  9. From IRAF, send  the image to display tool (ds9).
  10. Get z1, z2, and meanValue by doing imstat imageName.
  11. Type the command display imageName 1 zrange- zscale- z1=meanValue-2 z2=meanValue+10. This is done to detect the hotpixels on the full image.
  12. Now do imcopy imageName temp.
  13. Then imreplace temp 0 lower=INDEF upper=meanValue+10.
  14. Display this temporary image typing display temp 2.
  15. Once you are satisfied with the results, load the ctio package.
  16. Apply the command pixselect temp lower=1 upper=INDEF > temp.dat.
  17. Next command is fields temp.dat 1,2 > hotpix_g?p?.dat. Replacing the ? for the guider and probe respectively.
  18. Now copy the file hotpix_g?p?.dat into directory /home/mag#op/wavefront/. Where # is the operator's account.
  19. Remember deleting your working directory when the task has been done.
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