CCD and Imaging

Imaging System and Procedure:

  • Open CCD Soft: This program controls the CCD camera and displays the images you have taken. To take pictures with the CCD, select the “camera control” window and then the “setup” tab. Click “connect” to link the CCD to the computer.
  • Move the slide mirror out of the way of the CCD: Inside the telescope, the slide mirror reflects light from the tube into the eyepiece. When removed, light shines down into the CCD. To move the mirror, simply pull the silver rod to the side of the eyepiece. If the mirror is in place when you take an image, the image will appear as a white speckled picture.
  • Sync the telescope: Before taking any images, you must first make sure the telescope is synced correctly. Follow the guidelines in the basic operations guide to do so. You can use the CCD to take quick images to make sure your object is centered in the CCD frame.
  • Set the correct temperature: Make sure the CCD is operating at the optimal temperature. You can check this under the “temperature” tab.
  • Take an image: To take an image, set the exposure time, and set “series of” to how many pictures you would like to take. Make sure that the “frame” is set to “light” and “reduction” to “none”. Click “take image” to open the shutter. The resulting images will be automatically displayed in CCD Soft. Exposure times for common objects can be found here.

 

If doing research:

  • Create a folder on the computer for the night’s images.
  • Be sure to take note of all images taken as well as file names, object names, and air mass associated with each position (air mass can be found in Telescope Control).
  • Take darks: Once you have followed the above steps, you must take what are called “darks” for every “light” image captured. Under “image type”, select “dark”. The image will appear as (unsurprisingly) a black and speckled image that you will use to eliminate any noise in your light image. *Some advice – take a series of lights at a certain exposure time followed by a series of darks at the same exposure time, then move on to the next series of images.
  • Take biases: Though optional, it never hurts to take a few “bias” images. The item can be found under “image type”.
  • Take images of “standard stars”: Standard stars are stars with known brightness and luminosity used to set a baseline for the object in question. Follow the same protocol used to capture images of research objects to image standards. It is best to image standards in different areas of the night sky. Standards used in the past (specifically in the winter months) were SAO 14966, SAO 16848, and 27 Hyades. (Note that these may not always be the best to image).