Santa Barbara Instrument Group ST-5C, Operating Manual

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Section 2 - The First Day with the Camera
Page 17
and may be incorrect. Refer to the CCDOPS manual and the Telescope Setup and Edit
Parameters commands for more on this. This data will always be connected with the saved
image as long as it is viewed by any CCDOPS software such as a friend's or a magazine's.
5
Repeat the above procedures to capture, display and save images until you are confident
enough to take the next step of coupling your CCD camera to a telescope at night. This time,
before you exit the software, use the Shutdown command in the camera menu. You want to do
this before you pull the power to the CPU so that it has a chance to let the cooler warm up a bit
before the power is turned off. After using the Shutdown command give the CPU 30 seconds or
so before pulling the power. If you try to exit the software with the cooling on, the software
will prompt you to shut it down first.
2.2. The First Night with the Camera
Focusing a CCD camera can be a tedious operation, so a few hints should be followed. Before
using the software to focus the camera the first time, you should place a diffuser (such as scotch
tape, wax paper or ground glass) at the approximate location of the CCD's sensitive surface
behind the eyepiece tube and focus the telescope on the moon, a bright planet , star, or a distant
street lamp. This preliminary step will save you much time in initially finding focus. The
approximate distance behind the eyepiece tube for your CCD camera is 0.660 inches as shown
in the figure below.
Telescope
Back Focus
≈
0.660
Diffuser
0.660
CCD
Camera
Figure 2.2 - Camera Back Focus
Your CCD camera has a T-Thread on the front and is supplied with a screw-in 1.25 inch
nosepiece. Most users will find simply inserting the nosepiece into the telescope focuser in
place of the eyepiece the most convenient. Using the camera with other T-Thread accessories
like eyepiece projection adapters is also possible. At first, just use the nosepiece.
Orient the camera as shown in the figure below and drape the optical head's cable over
the telescope fork so that it is not hanging free and being dragged by the telescope which could
cause the telescope to have erratic RA (Right Ascension) motion. The orientation shown below
has the CCD's wide axis (X) aligned with RA and the narrow axis (Y) aligned with Declination.
Re-balance the telescope as required.
5
Note that it's always a good idea to display the image and adjust the background and range
parameters to your liking before you save the image. That way the CCDOPS software will remember
the settings and use them the next time you load and display the image.