An Astrophotography Primer
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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
Astrophotography is the use of
photography in astronomy; the
photographing of celestial objects and
phenomena.
Why astrophotography?
Tools and Techniques
There are four basic techniques
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,
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
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
Involves mounting a camera ‘piggyback’ to
a tracking telescope or other tracking
device to account for rotation of the Earth
Pros
Can take prolonged exposures
Relatively simple once setup
Cons
Requires tracking device (telescope/other)
Prime focus with Telescope
Involves replacing a telescope’s eyepiece
with a T-mount adaptor to directly connect
a camera to a telescope
Pros
Greater magnification
Less noise
Cons
Requires telescope and mount adapter
Tracking device nearly a must for deep space
objects
Telescope eyepiece projection
A camera replaces the human eye to
look through a standard telescope
eyepiece to capture an image
Pros
No adapter necessary
Alignment can be tricky
Cons
Requires telescope
Basic Types of Astrophotography
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
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
Stacking
What is it?
Early Astronomy usage and Brief History
Frames
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
Deep Space Example
Light Frame
Cropped Sample
Final Output
Deep Sky Stacker
Free to download and use
Advanced features
Best overview I found
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
Interesting Side Note
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
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
A Few Learnings
Focus can sometimes be tricky
Use Live View for precise focusing
Focus rings can be purchased to assist as well
ISO / Exposure time balance can be tricky
Don’t use less ISO just to reduce noise
Tracking can compensate for trails
Facebook groups have been very informative
and useful!!
Recommended Reading
http://www.astropix.com/GADC/GADC.HTM
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
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.