The Process

Astrophotography is a technically complex and challenging endevour that requires enormous patience and perseverance. However it is tremendously  rewarding when the skills and techniques are masterfully refined to create such amazing images of our universe from one's backyard.

What follows is but a brief attempt at encapsulating this process to aid in an appreciation of the final result.

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  Time, Patience and Perseverance

A single photograph is not a fleeting moment; it's    a   culmination of hours, sometimes   nights of work. 

  The universe  imp  oses its conditions;  light  pollution,  atmospheric   turbulence and   the ever-  changing dance     of celestial bodies. Each target demands   its own   allocation of time, from the swift  capture of the moon   to the prolonged observation    of distant galaxies requiring long exposure of the sensor.


The Planning

Determining which telescope and imaging equipment   to    use for the chosen target of t  he   night   made easier  with    software using planetarium   software   we can  pre-plan   this process weeks or months ahead.  Telescope  mounting   systems are typically equatorial   in design and  motor  driven systems  which will  track   the celestial arc during   the long   imaging runs. This   requires the mounting to be   polar aligned to calibrate    its position on   earth. The imaging   camera can then    determine its precise location to within    arc seconds      of accuracy before  the target can be captured   for   focusing and framing.

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Crafting the Ultimate Rig
Equatorial mounts ensure precise tracking of the night 
sky, compensating for Earth's rotation. Telescopes with  
high quality optics gather light with fidelity, enabling 
thecapture of fine details. The cooling of photographic 
equipment to sub-zero temperatures eliminates 
unwanted thermal noise, ensuring the clarity of the 
final image. Keeping dew at bay from the optics is
equally as important through the use of automatic
 sensing thermal dew heaters which track the relative 
dew point and ambient temperature at the optics.
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Focusing and Framing
Once the telescope has been calibrated for its position
 within the celestial sphere,  it can be slewed to the 
target using the onboard database to commence the 
framing. 
The framing can consist of a single frame or mosiac of 
frames depending on its size on the photographic 
sensor within the camera and size of the target to be 
imaged. 
Once framed, the appropriate  light pollution filter or
 other specialised spectral filter is placed in front of 
the camera sensor via the filter wheel. Automiatic 
focusing can then commence and specialised software 
will  ensure  sharp critical focus is acheived  within 
given atmospheric conditions. 
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Acquisition 
Capturing the light from a deep sky target, that has 
travelled vast distances through time and space 
requires numerous long exposure frames to be taken 
and then meticulously stacked and aligned.  Imaging 
runs typically are measured in several hours on perfect 
still dark nights, using dedicated cooled astronomy 
cameras controlled by on-board computers. 

As the night gets colder, critical focus changes, which
 forces the auto focuser to re-focus based on 
temperature and humidity changes that are sensed
 near the camera throughout the night. Critical focus 
is measured in terms of less than the thicknesses of a 
human hair. Any voltage supply fluctuations  have 
minute effects on the mount's drive systems. These 
impepections are smoothed out through a second 
telescope and camera mounted on the main imaging 
telescope. This second telescope locks onto 
guide stars within the target to assist the drive 
systems to refine their movements to cancel out any 
voltage  & minor alignment calibration errors. The 
precision required in tracking and guiding systems is 
paramount, essential for preventing distorted or 
elongated stars. Light pollution filters and the
removal of dust particles are introduced as
 measures to ensure the clarity and accuracy of the
final images. Tracking & guiding must stay within 
1 to 2 pixels of accuracy for any given frame. 
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Post Acquistion
Once the required frames are taken and saved, the 
presence of dust particles inherent in any optical 
system of lenses, filters and camera sensors, must 
be digitally removed to ensure the clarity and 
accuracy of the final images. The meticulous 
calibration process, involving dark and flat frames,
 is a crucial step in enhancing image quality.
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Post Processing Software & Data Handling
Powerful computing resources are essential for 
handling the vast amounts of data generated during
 imaging sessions. 
Due to the large file sizes of each frame, cloud storage 
is utilised to capture the gigabyte amounts of data 
which can be captured on a given night.

The post-processing phase adds yet another layer 
of complexity, transforming the raw data into the 
vibrant, detailed images that grace the final frames.
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Sharing the Wonder
As you gaze upon these images, remember the journey 
behind them. The nights spent under the stars, the
 hours of processing data, and the countless moments 
of awe that connect us to the universe. These 
photographs are a tribute to the cosmos, a testament 
to the human spirit's boundless curiosity and the 
power of technology to bridge  the gap between 
Earth and the heavens.