MAKEE: Controlling the Object Extraction Boundaries (as November 2000)

MAKEE will centroid on the brightest object in the slit, compute offsets as a function of order# relative to the trace star, and determine the object boundaries by attempting to encompass a given percentage of the flux (usually 98%, see parameter files ). The boundaries selected can be seen in the output file. Sometimes the default boundaries are not desirable in some cases (e.g resolved sources). In these cases, it is possible for the user to control the object and background boundaries using the "hw=", "oko=", or "uop=" options in MAKEE.

"hw="  :  This option controls the half-width of the object. If you use this option, the object centers will be determined automatically but the half-width (center +/- half-width) will be set to the value given by "hw=". The value is given in pixels. See the plot to estimate your desired half width.

"oko="  :  This option tells MAKEE to only use certain orders when determining the object centers and half-widths. Normally, MAKEE will fit a 0th or 1st order polynomial to the computed object centers for each order, however sometimes there are very faint orders which will cause mess up this polynomial fit. In particular, this can occur with ESI when observing a very red object, and there are only 3 or 4 orders with adequate light. To use this option specify all "ok" orders separated by commas. Remember that the bluest-most order is always number 1. The following example:

will tell MAKEE to only use orders 6, 8, and 9 when determining the object centers and half-widths. NOTE: You must specify at least 2 echelle orders.

"uop="  :  This option tells MAKEE to use the information in a user created ASCII file to determine the object and background boundaries. With this option, it is possible to extract parts of a resolved object or extract two or more objects on a slit (run MAKEE once for each object). A description with examples is given here: uop_help .

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