6. Introduction to PARD Capture
Correctly mounting the camera over the eyepiece (as described in chapters 3 and 5) is
essential for taking good images but, in itself, is not sufficient. The AF51 camera has a
range of settings (described in chapter 3) which need to be set appropriately to the type of
image acquisition needed for different purposes. In addition there are particular image
acquisition techniques, such as multi-frame averaging, dark current correction, flat field
correction, etc., which need to be performed to get the best possible images for scientific
applications.
Failure to select the correct camera settings and failure to adopt the correct image
acquisition procedure can result in images of disappointing quality. Not all the software
packages discussed in chapter 4 allow for optimal image capture for scientific
processing. For example, none of them allow you to capture only the monochrome Y
channel of the YUYV frame (and that is important to avoid artefacts that occur in the
colour signal readout of the AF51 in low light conditions – see chapter 7 for more on
that). The free and open source PARD Capture software, on the other hand, was
specifically designed for optimal image acquisition for scientific image capture
(including Y-only images) and this chapter will take you through the basics of its usage.
Chapter 7 will give some practical tips for optimal quality image acquisition and show
example images.
PARD Capture uses the v4l2 API to control the default video device on the system
(/dev/video0) so it may work with many different cameras. However it was optimised to
work with OptArc camera so some other cameras may not be compatible. In order to be
useable with PARD Capture a camera must be able to stream images in either MJPEG
or YUYV or both image formats. Furthermore PARD Capture cannot use video frame
resolutions with a height of 288 or 144 pixels so if you camera supports these
resolutions you will not be able to use those particular resolutions with PARD Capture
(they will not be offered to you in the list of available resolutions).
For more information about PARD Capture and to get the latest version of the source
code, see the project GitHub page:
https://github.com/TadPath/PARDUS/tree/main/PARD_Capture
OptArc AF51 Camera Page 60 of 99 User Guide v1.02