Santa Barbara Instrument Group ST-5C, Руководство по эксплуатации

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Section 2 - The First Day with the Camera
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To position the planet frame with the mouse, click and drag the upper-left and lower-
right corners of the box or click and drag the center. To position it with the keyboard (DOS
only), you use the arrow keys in combination with the T key. The T key toggles whether you
are moving the Center, the Upper-Left or the Lower-Right corner of the box. You can see which
is currently selected in the upper-left corner of the display adjacent to the Hot label. Once you
have placed or redrawn the box, proceed with the Focus command by hitting the L key (for
located).
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You achieve critical focus by watching the Peak value displayed in the upper-left corner
of the display (DOS) or in the Focus Window (Win 95 & Mac) and adjusting the telescope focus
until the highest peak value reading is achieved. We recommend you start on one side of focus
and adjust the telescope a little at a time. On the first pass just get a feel for what sort of peak
reading you'll be able to achieve and don't worry if you go past the peak. In fact, make sure you
have gone through the peak and the peak values are dropping off or the star image is
deteriorating. Then back up the focus and go through it again, this time stopping when you get
close to the peak readings from the first pass. For SCT's always approach exact focus with a
counter-clockwise focus knob movement.
2.2.2. Finding and Centering the Object
Once best focus is achieved, we suggest changing the Focus command to the "Dim" mode to
help center objects. This mode gives a full field of view, increased sensitivity, but reduces
resolution in order to increase the digitization and download time. If you have difficulty
finding an object after obtaining good focus, you can remove the head and insert a medium or
low power eyepiece. Being careful not to adjust the focus knob on the telescope, slide the
eyepiece in until the image appears in good focus. Then visually find and center the object, if it
is visible to the eye. If not, use your setting circles carefully. Then, re-insert the CCD head and
set an exposure time of about ten seconds. Center the object using the telescope hand controls.
Remember, your CCD chip is only 2.4 x 3.2 mm or the size of a match head. This field of view is
like using a 4-6 mm focal length ocular!
Note: With a 10 second exposure, objects like M51 or the ring nebula are easily detected with
modest amateur telescopes.
2.2.3. Taking an Image
Take a CCD image of the object by selecting the Grab command and setting the exposure time
to 60 seconds. Set the Dark Frame option to Also so the software does an Auto-Dark
subtraction, set with Image size to full and enable Auto Display. The camera will expose the
CCD for the correct time, download and then display the image. You can then save it or keep
trying your acquisition and focusing technique
When you are through for the night don't forget to use the Shutdown command in the
Camera Menu before you pull the power on the CPU.
2.3. Further Foray’s into CCDOPS
The CCDOPS software that comes with the ST-5C has many capabilities and will serve you well
in your imaging pursuits. At this time we refer you to the separate CCDOPS Software manual
for guidance and detailed technical information on that software’s capabilities. Section 3
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You don't have to remember all the key names. The CCDOPS software has a pull down menu in the
upper-left corner of the display (named Focus in this case) that you an click on with the mouse or pull
down with the Enter key. You can then make choices from that pull-down menu.