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3.8 Centering the X-Y Stage

Centering the X-Y stage is important for some projects but not for others, so it’s your decision as to whether to do this or not. If you wish to center the X-Y stage, it is conveneint to do so while you are on the bright star you indexed on. Centering the X-Y stage also centers the guide camera.

Make sure that the Guide Camera (outlet #4) is ON in the power outlet web page, then go to the video cameras page in the Auxiliary Instruments window and select the guide camera. The Mirror Slide and X-Y Stage controls are also in the Auxiliary Instruments window. Move the Mirror Slide IN, then Initialize the X-Y Stage. Then move the X-Y Stage back On Axis using the appropriate buttons in the X-Y Stage window. Make sure the intensifier is turned all the way down (to the left), then turn it on. Slowly turn up the intensifier until you see the star in the video screen.

Caution: Be careful of turning up the gain on the intensifier too high on a bright star or when there are lights on in the dome. Flooding the intensifier it with too much light could easily burn it out.

Once you see the star you can center it in the video screen using the X-Y Stage directional buttons. The step size can be adjusted with the box in the middle of the direction buttons. Ideally, the X-Y stage center (0,0) is also at the center of the CCD, but this isn’t always the case. After you center the star in the video screen using the X-Y Stage buttons (NOT the soft Hand Paddle buttons- that will move the telescope!) make a note of the (X,Y) coordinates of the center of the X-Y Stage (and hence the guide camera) for the night.

Note: East and West are flipped on the X-Y Stage interface.

Move the Mirror Slide OUT of the path of the light when you are ready to take images with the CCD.
Turn the intensifier gain down and off when you’re done with it.


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Next: 4 Observing Previous: 3.7 Indexing


Updated: 2/10/99