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CCD Field of View using Albireo

EL Obs 2

SPU-21 Fall 2015

Let's determine the CCD field of view! Using the known separation of the double star, Albireo (34 arcsec - given in the Visual Observations of Albireo lab), we can determine the size of the CCD in arcminutes.

Procedure:

- Slew the telescope to Albireo RA=19:30:43 DEC=+27:57:40
- Take a very short (0.1 sec) exposure, making sure not to saturate the image. If necessary, use the Aperture Mask to essentially make our telescope aperture smaller and allow a longer exposure on the CCD before it saturates.
- Load the image you took above in MaximDL
- Measure the X, Y pixel coordinates of each of the 2 stars by hovering the curser on the center of each star in turn and then recording the X,Y coordinates in the table (pdf or docx).

Analysis:

- Star 1 has coordinates (X
_{1}, Y_{1}) and star 2 has coordinates (X_{2}, Y_{2}). - Consider the difference between stars (in pixels) the distance, Z, where Z = ((X
_{1}-X_{2})^{2}+ (Y_{1}-Y_{2})^{2})^{ 1/2}[Do you recognize this equation? The hypotenuse of a right triangle!] - When you divide this by the separation between the stars (34 arcsec), this gives you the number of arcsec/pixel on your CCD image.
- Determine the number of pixels your CCD image contains in X, Y by roaming the curser from one side of the image to the other.
- Since you now have the conversion of arcsec/pixel, use this to find the corresponding size (in arcsec, and then convert to arcmin) of the full CCD.