Using The Camera; Establishing A Link With Ccdops; Camera Setup; Taking Sample Dark Frames - SBIG STX Series Operating Manual

2.2. Using the Camera

This section gives you a quick introduction to using your Camera with CCDOps. Further
information can be found in the CCDOps Manual on the CD ROM.

Establishing a Link with CCDOps

In order to control your Camera, CCDOps you must first establish a communications
link with the camera as described below:
• In the Windows Start menu navigate to the SBIG folder then select the CCDOps
icon to launch CCDOps.
• Under CCDOps' Misc menu select the Graphics/Comm Setup command.
• Check to make sure the Interface item is set for USB then click OK.
• Under the Camera menu select the Establish COM Link command.
• In a few seconds CCDOps will establish a link to the camera as indicated by the
Link status field in the lower right hand corner of the CCDOps window:

Camera Setup

The Setup command in the Camera menu is used to configure the Camera's internal
operating modes. As an example let's use it to turn on the cooling. Invoke the command
and then set the Temperature Regulation item to Active and the Setpoint item to 0.0
then click OK. You'll see the Camera start to cool down as indicated in the Temp status
field.

Taking Sample Dark Frames

Dark Frames are used in Astronomical CCD Imaging to reduce the noise of images by
subtracting out fixed pattern noise inherent in the CCDs. Let's take a Dark Frame with
the main or Imaging CCD to see what it looks like:
• Cover the camera so no light is getting into it through the Telescope Coupling.
Cover the camera with a book or turn the camera over and place it on its face.
• Use the Grab command in the Camera menu. Set the Exposure to 1.0 and the
Dark frame to Only then click OK. After several seconds the image will appear
on the screen.
• In the Contrast window make sure Auto is checked and the Mag is set to 1:1.
• Scrolling around in the image and inspecting it visually you'll notice how large it
is (4096 x 4096 pixels) relative to your computer screen. You'll also see areas of
"salt and pepper" that represent the noise floor or Read Noise of the CCD and
you'll see numerous bright or Hot Pixels. You'll probably see some Hot Pixels
with tails below them. These are in every CCD camera and repeat from image to
image. By subtracting Dark Frames from your images you'll remove these
effects from the final image.
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