DOFPIA Command Line flags and parameters

The following list is excerpted from an email to the LBC list from John Hill.
All LBC observers should be using DOFPIA, and not LBCFPIA by itself. Not only does DOFPIA save time, but LBCFPIA has been tweaked so it converges to the non-optimum Z11 value with larger central hole.

DOFPIA now has the following command line flags and parameters:

• /X2 - double the automatic OB exposure times from 16 sec to 32 sec. Use /X2 for clouds, high dome seeing, or fields with faint stars.


• /RedOnly - only work on LBC-Red
• /BlueOnly - only work on LBC-Blue


• RedLimit=value - convergence limit for Red (default is 400 nm)
• BlueLimit=value - convergence limit for Blue (default is 400 nm)
• Increase these limits to 600 nm or more when the dome seeing is bad, or if you are doing standards and don't care about excellent image quality.


• RedInitial=value - initial quantity of Z11 to send (default is 500 nm)
• BlueInitial=value - initial quantity of Z11 to send (default is 600 nm)
• Increase these Initial values to 1200 nm in bad seeing to make the central obstruction more visible in the extrafocal pupils. This can improve convergence on the other Zernike terms. In superb seeing, you may want to make the initial offsets smaller.
• /First sets RedInitial and BlueInitial to larger values appropriate to the initial collimation and/or poor seeing.


• /BackOut causes DOFPIA to remove initial Z11 values sent to the primary mirrors.Use this to remove the extra Z11 if something like clouds made the loop fail. Simply replay your previous DOFPIA command with the /BackOut flag added. No images will be taken as the program exits after removing the corrections.


• MaxIterations=value - stop DOFPIA after this many iterations (Fernando's request)


• /Sim - run it in simulation mode without taking images (not for observing)


• The experienced LBCFPIA user may want to stop before perfect convergence. Now, typing an 'S' (uppercase-S) while DOFPIA is running will cause it to exit and send the final Z11 corrections after it finishes the iteration that is running.


• If the seeing is bad, so that the estimated seeing is more than 2.0 arcsec, then LBCFPIA sends no Z11 corrections. In this instance, DOFPIA is clever enough to back out the initial Z11 correction, and not send a final offset from a psuedo-corrected position. (This code is there, but has not been tested on sky as seeing was too good.)