Focusing the ST7

To achieve a sharp focus, start with the "dim" mode with auto contrast "on" and point the telescope at a bright star. An out of focus star shows as a round white doughnut. Focus until the dark center disappears and other stars start to come into focus. Switch to "planet mode" and select a group of stars close to the middle of the frame. In "planet mode" you can size and place a box around the target stars. A small box will enlarge the star's image so minute changes can be seen as you focus. Attempt to obtain bright round circles with no central obstruction showing. Also watch the pixel values in the upper left box. As the light is intensified on the chip the values will increase. If the values increase then start decreasing, you have gone on the other side of focus. Always come into focus turning the focus knob counter-clockwise as this keeps tension on the mirror. Try to obtain the highest pixel value possible.

After focusing the next step is to calibrate the drives.

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