When examining images of objects collected by digital image devices,
it is important to understand the underlying processes before you can
interpret the output images. The introduction of electronic circuitry
and computational approximations in the image process introduces
electronic factors and conversion and data errors that we need to take
into account when examining the digitized data coming from the imaging
device. Electronic factors include the bias, dark current, and read
noise that are all contributed within the CCD due to both how the data
is read out electronically and the inherent properties of the CCD
itself. Conversion and data errors occur when the CCD converts the
collected data to digital data. We found that our CCD has a dark current of about
1
at -20
C, a bias of 1407.29 DN, a
read noise of about 5 DN, and a gain of about 1.5
. We also found that the CCD saturates when
our pixels contain about 98,300
. The techniques we develop and the
properties determined in this lab are important when taking
astronomical data and images as it pertains to the study of stellar
and galactic photometry.
