Karen Gloria wrote the following in last night's observing log, and it seemed appropriate to post it to this wider distribution: ***************************** I'm including some detailed notes on the DSC here because this information is important to anyone planning to use it. The DSC: I acquired a new instrument block and tested the new TCC and MC drift-scanning code. The orientation of the DSC chip is EAST on the RIGHT, NORTH on the BOTTOM (on the SCROLLING DISPLAY). The orientation is north on the top, east on the right in IRAF displays (ximtool, saoimage). TCC instrument offsets: A +X offset moves the star to the RIGHT. A +Y offset moves the star to the BOTTOM (on the SCROLLING DISPLAY). When the object rotation is 0, a +X offset will move the TELESCOPE WEST (star moves toward the east side of the display). A +Y inst offset will move the TELESCOPE SOUTH (star moves toward the north side of the display). REMARK instrument offsets: A +X instrument offset issued through the Remark interface moves the star to the LEFT (the TELESCOPE moves EAST if the object rotation is 0). A +Y offset moves the star to the TOP (the TELESCOPE moves NORTH if the object rotation is 0). Rotation: A + rotation issued through the TCC will rotate the FIELD CLOCKWISE on the scrolling display (counter-clockwise on an IRAF display). Drift-scanning: To drift scan, issue an offset of 0,-y (i.e. drift northward). I tested Russ Owen's new TCC driftscanning commands. They work just fine. These TCC commands are: TRACK/SCANVELOCITY=(VX,VY) The velocities are in units of degrees/sec and should correspond to the fractions of siderial rate that the camera uses (i.e. 0.0016667 deg/sec for 0.4 siderial rate). This command will drift along a great circle. OFFSET ARC=N (where N is a value in units of degrees). If you want ot drift along a small circle, issue this command before the track/scanvelocity command. It will offset the telescope onto a small circle parallel to the great circle it would have drifted on (this is hard to describe without a diagram). I tested both of these commands and the drift scans came out very good - all round star images. I also tested Brian Yanny's new MC drift-scanning commands. These also worked fine. They are: offset vx vy drift (vx and vy are in units of DEGREES/HOUR) If you want to drift scan at 0.4 siderial rate, for example, use: offset 0 -6.0 drift (6.0 = 0.4 siderial in degrees/hr) offset 0 0 drift stops the drift I tested this and the drift scans came out just fine. DSC operation: I ran into a few small problems with this- the commands displayLast and getLast don't work (this is mentioned in the documentation.) I wasn't able to get an saoimage window open on fnstar. If you get error messages about the murmur server not running when you start up, exit to the unix prompt and type ps -ef | grep mur to see if the two murmur processes are running. If they aren't, type dscRun start_mursrvr (then type dscRun) - This is ommited from the current version of the documentation. The runAutoFocusSequence command doesn't write the frame to your data area, so after it finishes type: saveFiles group start finish directory (insert your group name, the sequence # of the first frame you want, the sequence # of the last frame you want, your data directory path) The killCameraShell command doesn't work. To kill the control shell when you are done, use: killControlShells then type quit (or exit). The error "timing active" cropped up a few times, preventing me from taking any exposures. Reseting the VME crate clears the problem. APO APO APO APO APO Apache Point Observatory 3.5m APO APO APO APO APO This is message 45 in the apo35-general archive. You can find APO the archive on http://astro.princeton.edu:82/apo35-general/INDEX.html APO To join/leave the list, send mail to apo35-request@astro.princeton.edu APO To post a message, mail it to apo35-general@astro.princeton.edu APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO APO