Usage

guider [time=] [centroid] [box=sr,sc,nr,nc] [nbytes=] [bin=]

Time is given in seconds. If the centroid keyword is specified, then a return value similar to:

> tx guider time=3 centroid
done guider row=111.82 col=109.22 sum=651 sky=5.8

row

refers to the row of the centroid of the image.

col

refers to the column of the centroid of the image.

sum

is the total number of counts above the `sky' value.

box=

sets the size of the box.

bias

takes a bias frame.

nbytes=

initiates the image transmission. If no exposure time was specified, then the previous image is transmitted.

When a centroid is calculated, a bias exposure is taken (one with the same exposure time and no shutter) and this is subtracted from the data before the centroid is calculated. A new bias frame is made whenever either: the box size is changed, the exposure time changes by more than 0.1 second, or the bias keyword is specified. The image can be confined to a smaller box by using the box command and specifying the starting row sr, starting column sc, number of rows nr, and number of columns in the box option nc. If none of these keywords are present the entire chip is used. NOTE: The maximum guider exposure is 60.0 seconds.