Reference File
==============

The ``guider_cds`` step uses two reference file types: :ref:`GAIN <gain_reffile>`
and :ref:`READNOISE <readnoise_reffile>`.

Both the GAIN and READNOISE values are used to compute the total error
estimates. If either reference file is inaccessible, representative default
values will be used.

:ref:`GAIN <gain_reffile>`

:ref:`READNOISE <readnoise_reffile>`