Deep Sky Astrophotography
What am I Doing?
Howard C. Anderson
25 July 2014
http://www.astroshow.com
Overview
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Location (Dark skies help)
Observatory
Hardware
Software
Figure out what to shoot
Shoot images
Process images
Location
• Dark sky helps a lot. Main reason for locating
remotely…
• My observatory is in New Mexico south of Lordsburg
where we have really dark skies.
• Bernard’s observatory is close by as are several others
including Eric Africa’s both of whom take truly excellent
images.
• I didn’t know remote operation was possible until I saw
Bernard Miller’s presentation at an EVAC meeting some
time ago… I used his presentation as a guide:
http://www.azstarman.net/remote_observatory_web.ppt
• I’m still learning image processing – Maybe always will
be…
Rancho Hidalgo – ~250 Miles
Observatories at Granite Gap
Observatories at Rancho Hidalgo
My Observatory at Rancho Hidalgo
Hardware
• Meade LX-200 10”, SBIG STL-11000 Camera, Astrodon
filters for LRGB and Hydrogen Alpha, water cooling
system for camera (CPU over-clock cooler), Optec TCFsi focuser.
• Takahashi TOA-130 (5 inch) refractor, SBIG ST4000XCM single-shot color camera, Celestron CGE
mount, Optec TCF-si focuser.
• 32-bit PC computer running Windows 7
• Foster roof control board
• 4 inside video cameras so I can see position of the roof
and the scopes (… Just in case…)
• Foster weather monitor (clouds, temperature, wind)
Software
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Remote Desktop (Free) (Operate remote computer)
http://nova.astrometry.net (All-sky plate solver)
TheSkyX Pro (Display sky, choose objects to shoot, get coordinates)
VMware Workstation (Computer within a computer so to speak)
Foster Dashboard (roof control) and AstroAlert (weather)
Web Power Switch (Turn stuff on and off)
NexRemote (Celestron CGE control software)
ACP Observatory Control Software (Controls roof, scope, camera)
Maxim DL imaging software (camera control, image processing...)
FocusMax (Freeware) (Automatic focus system)
CCDStack (Image processing. Best deconvolution algorithm)
eXcalibrator (Freeware) (Color calibration using known star colors)
Photoshop (Image processing – Essential, expensive, hard to use)
Paint Shop Pro (Image processing software)
Software I wrote: CheckPorts, ComputeFocus, FixBadPixels, etc.
Web Power Switch
CheckPorts
Attention Span Relief
Your secrets are safe in England
Roof and Weather Check
Cameras Inside Observatory
Remote Desktop view of Virtual Machine
ComputeFocus
Optec Focuser
TheSkyX Pro Mosaic
ACP Script to automate mosaic imaging
of Pelican Nebula Target
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#waituntil 0, 02:30:00; UTC == 7:30 PM
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#domeopen
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#waituntil 0, 05:30:00; UTC == 10:30 PM
#chill -10
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#autofocus
#AFINTERVAL 60
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;Pelican Nebula mosaic region.
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#sets 2
#count 1
#interval 1200
#binning 1
Pelicana 20.89081215 44.46455987
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#count 1
#interval 1200
#binning 1
Pelicanb 20.81334255 44.46455645
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#count 1
#interval 1200
#binning 1
Pelicanc 20.89027385 43.63525503
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#count 1
#interval 1200
#binning 1
Pelicand 20.81388148 43.63525166
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#shutdown
Run the Script in ACP
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I start script running in ACP
Script waits until time I say it should start doing things
Opens roof (allows things to cool down - summertime)
Waits again until specified time to begin imaging
Sets camera temperature and waits until camera
temperature is what I specified
• FocusMax then finds a suitable star, moves scope, and
focuses camera
• I told it to refocus every hour. It does that automatically
between shots
Run the Script in ACP
• After focus, ACP moves scope back to designated object
• ACP takes 30 a second image, plate-solves, moves
scope dead-on
• ACP then runs auto-guider subsystem and starts autoguiding
• If guiding is OK, ACP starts taking an image using the
exposure time I specified (1200 seconds in this case,
i.e., 20 minutes)
• ACP will take all the images I specified, refocus
periodically between images, and store the images in a
default location
• I will be sleeping during this… I am a “morningperson…” 
ACP Image Folder for Pelican Target
(Single-Shot Color Camera)
Attention Span Relief
Victor Borge
Single-shot color cameras
Bayer Mask
You initially have a gray image that needs to be
CONVERTED to RED, GREEN and BLUE gray images
which are then combined to give a full color image…
(Green light contributes roughly twice as much to our
perception of brightness than does the combined effect of red
and blue.)
My Video Monitor
Red, Green and Blue Images
Combine RGB
images to get
color image
Small star on monitor
- magnified…
Example: IC4865 - FixBadPixels (i.e., color
convert, calibrate) Then Stack – Image Excerpts
Single Original
Single Original Fixed
10 Fixed, Stacked
300X Excerpts to Show Improvements
Single Original
Single Original Fixed
10 Fixed, Stacked
Transfer Stacked Image from Observatory computer to
local computer and start image processing
• In Maxim DL, “Convert to Mono” to create Luminance (L) image
• Use CCDStack to deconvolve the L image
• Deconvolution is a process that undoes the "blurring" obtained after
convoluting data. See http://en.wikipedia.org/wiki/Convolution
• Save the deconvolved image as the new L image
Correct color using eXcalibrator
• In Maxim DL “Split Tricolor” to create Red, Green and
Blue images (If I start from a full-color image)
• Do “Pinpoint Astrometry” (plate solve) Red image and
save it (Creates World Coordinate System (WCS) data)
• Use R, G, and B images in eXcalibrator. Use R image
as WCS image
• Use NOMAD database
• “Calibrate Image”
• “Remove Outliers”
• Get correction values for R, G and B images
eXcalibrator Color Correction Coefficients
Combine LRGB with Color Correction
• In Maxim DL, combine LRGB images using the correction values
• Save image as a 16-bit TIFF image for use with PhotoShop
Attention Span Relief
Remote Control Roundup
Photoshop Processing
• Read in 16-bit TIFF image
• Looks pretty dark
• Use “Curves” successively to brighten (as
recommended in “Photoshop Astronomy”)
PhotoShop “Curves”
Successive Curves
Levels Adjust
• Use Levels to adjust dark level
Photoshop Add-on:
Astronomy Tools V1.6
• I apply “Make Stars Smaller” 3 times usually.
• I apply “Space Noise Reduction” and “Deep
Space Noise Reduction as needed to reduce
graininess of the image.
• I apply “Increase Star Color” until I am happy
with star colors.
• Then additional tweaking of Curves and Levels
in PhotoShop until I am happy with amount of
detail visible.
Additional PhotoShop Operations
• Vibrance:
• If I err, it is on the side of too colorful I
guess… I like color…
Vibrance Result
Tweak Curves, Levels, Vibrance, etc., in PhotoShop then save as JPG
Paint Shop Pro
Final tweak of brightness, contrast, etc., resulting in this:
http://www.lightfigures.com/DSS2
Pelican Mosaic (4 images)
M51 – Whirlpool Galaxy
Cone Nebula
Flame Nebula and Horsehead Nebula
M109 and Flashlight of God
Finis
• See my images at:
http://www.astroshow.com
• Questions?