Transcript An Astrophotography Primer

Jeff Arrington & Bryan Phillips
Agenda
Overview of Astrophotography
 Tools and Techniques
 Basic types of Astrophotography
 Advanced Tools and Techniques

Overview of Astrophotography
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Astrophotography is the use of
photography in astronomy; the
photographing of celestial objects and
phenomena.
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Why astrophotography?
Tools and Techniques
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There are four basic techniques
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Tripod photography
Piggyback/Tracking photography
Prime focus with Telescope
Telescope eyepiece projection
The tools required depends on technique and desired outcome
 A camera (point and shoot, DSLR, iPhone, Droid, CCD, web camera,
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etc.)
Tripod/Mount
A star chart
A clear night
A plan
Telescope with appropriate mounts (optional)
Tracking device (optional)
Post Processing Software (optional)
Tripod Photography

Tripod photography facilitates the use of a camera
stabilized on a tripod for steady imaging
capabilities – remote shutter preferred

Pros
 Least amount of equipment necessary
 Great starting point to get into the hobby
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Cons
 Images may need some post-processing for best results
 Less Magnification = more concentrated noise
 Cannot account for star trails and rotation/movement
Piggyback/Tracking photography
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Involves mounting a camera ‘piggyback’ to
a tracking telescope or other tracking
device to account for rotation of the Earth
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Pros
 Can take prolonged exposures
 Relatively simple once setup
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Cons
 Requires tracking device (telescope/other)
Prime focus with Telescope
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Involves replacing a telescope’s eyepiece
with a T-mount adaptor to directly connect
a camera to a telescope
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Pros
 Greater magnification
 Less noise
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Cons
 Requires telescope and mount adapter
 Tracking device nearly a must for deep space
objects
Telescope eyepiece projection
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A camera replaces the human eye to
look through a standard telescope
eyepiece to capture an image
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Pros
 No adapter necessary
 Alignment can be tricky
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Cons
 Requires telescope
Basic Types of Astrophotography
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Wider Angle
 Constellations
 Moon
 Comets
 Sun
 Galactic Center
 etc.
Deep Space Photography
 Messier Objects
 Other Nebulas
 Planets
 Asteroids
 Galaxies
 Etc.
Wider Angle Example
No need to for 0 light pollution but the
less is better.
 Before Processing
 After Post Processing
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Post Processing sample
 How to edit the Milky Way - Photoshop Tutorial
Advanced Techniques
Advanced techniques build upon the
basics
 Often require advanced filters, cameras,
lenses and mounting equipment
 Often requires post processing
 Stacking, contrast, color correction are
just a few of the post processing actions
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Stacking
What is it?
 Early Astronomy usage and Brief History
 Frames
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 Dark Frames
 Light Frames
 Bias Frames
 Astrophotography without a star tracker
Process
Setup
 Light Frames (typical exposures)
 Dark Frames (same as light but with
lens cap on)
 Bias Frames (same as light but with
fastest possible speed)
 Dark Flat Frames, Offset Frames
 Deep Sky Stacker
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Deep Space Example
Light Frame
 Cropped Sample
 Final Output
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Deep Sky Stacker
Free to download and use
 Advanced features
 Best overview I found
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 https://www.youtube.com/watch?v=e0JSTF8SGi4
Deep Sky versus Local Solar Objects
Stacking Methods are different
 Deep Sky Stacker is for deep space
objects (nebula, galaxies, etc.)
 Registax is proclaimed to be one of the
more popular stacking programs for closer
objects (i.e. planets)
http://www.astronomie.be/registax/
 Fitswork is another
http://www.fitswork.de/software/softw_en.p
hp
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Interesting Side Note
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I am certain you could imagine Eastman
was somehow involved in imaging and
astrophotography right?
 Brief History of Astronomical Photography
 Kodak plates were used longer than you might think and had a
great impact leading to many astronomical discoveries. The
discontinuation of them in 1993 as well as the advancements in
digital technology has drastically driven the rise of CCD cameras
in place of Kodak emulsions (reference).
In Conclusion
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No need for expensive telescope, mount,
camera, etc. to get started
 You can even just use the internet!!! (Rent and
shoot online)
Post processing although helpful is not
necessary
 For canon RAW format I needed the Deep
Sky Stacker version 3.3.4 at
http://deepskystacker.free.fr/download/Dee
pSkyStacker334.rar else there was an
issue processing the Canon RAW format
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A Few Learnings
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Focus can sometimes be tricky
 Use Live View for precise focusing
 Focus rings can be purchased to assist as well
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ISO / Exposure time balance can be tricky
 Don’t use less ISO just to reduce noise
 Tracking can compensate for trails
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Facebook groups have been very informative
and useful!!
Recommended Reading
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http://www.astropix.com/GADC/GADC.HTM
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I have a few books you are more than
welcome to borrow
 Digital SLR Astrophotography – Michael A Covington
– More applied learning
 The Deep-Sky Imaging Primer – Charles Bracken –
Good Technical resource
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I also highly recommend joining the Facebook
group ‘Telescope Addicts-Astronomy &
Astrophotography Community’ – finding this
sooner would have saved me time, money and
given me some better ideas.