User Tools

Site Tools


vatt:collimate_vatt

Collimate VATT

To collimate, and initialize the telescope, send the telescope to a bright
star (5--7 mag). Take a very short exposure with the science camera (0.1sec).
If the star does not appear in the center of the CCD, adjust the telescope
pointing with the "Paddle" buttons until it does.  Then move the "Center"
mirror in so the guide camera can see the center of the FOV. When the noise
of the servos stops, change all "Pos.Input" and "User offset" values to 0.
Collimate the telescope by changing the guider focus to -25 or so, then 
adjusting the "TipX" and "TipY" values until the hole in the out-of-focus
stellar image appears in the center of the "donut" and the distribution of
the light is symmetric. When collimated, set the focus back to zero and
adjust the "Pos.Input" values until the stellar image is centered into the
field of view of the guide camera.  Then hit the "Init. Coords" button at
the top of the main TCS GUI window to set the commanded coordinates for the
star equal to wherever the telescope is currently pointing and adjust the
pointing model accordingly.  
NOTE: Do not hit the "Init. Coords" button again after manual offsets with
the paddle buttons during subsequent observations to move a target off of a
bad column or region of the science CCD, since this would guarantee not
being able to find another guide star during the remainder of the night!
  1. —————> Let the science observations begin… ←—————
vatt/collimate_vatt.txt · Last modified: 2012/09/14 12:36 by admin