Astrophotography,
believe it or not…
…is not as hard as rocket science.
It’s not rocket science.
•
•
•
•
•
•
•
No Physics degree required
No Computer Science degree required
No Engineering degree required
Some computer skills can be useful
Some mechanical ability is useful
A basic understanding of electronics is useful
Some understanding of the underlying
science is a great plus
• While equipment continues to improve, the
core technology itself is reasonably mature –
it is highly unlikely that you will need to invent
anything in order to be successful
• Patience and perseverance are absolutely
mandatory!
It’s not black magic, either.
It’s not black magic.
 understanding the critical elements
involved leads to better results
 a little simple math can greatly assist in
understanding how things work as well
as what you might expect as a result
 using practical and measurable
considerations when making
equipment choices will ultimately
simplify the job
 taking the time to develop a logical and
tested workflow will improve your odds
of repeatable results
How Solar System Imaging differs from
Deep Sky Imaging
• most objects are generally
much brighter than DSO’s
• good results can be achieved at
relatively fast shutter speeds
• highly effective cameras are
generally much less expensive
than purpose-built astronomical
CCD cameras
• accurate tracking is not as
critical to success – guiding is
completely unnecessary
• good results can be had using
moderately priced telescopes
and mountings with
uncomplicated setups
• trips to dark sky are not
required in order to get good
results
How Solar System Imaging differs from
Deep Sky Imaging
• the details we are trying to
capture are generally much
smaller in apparent size than
DSO’s
 longer focal length instruments
are useful for best results
 telextenders (“powermate”,
barlow and/or extension tubes)
are very helpful in increasing
image scale
• larger aperture instruments
help overcome light loss due to
the high focal ratios involved
• much more susceptible to poor
seeing, focus and collimation
Cameras
Solar System Cameras
Philips ToUcam Pro 740K
• No longer in production but widely
available used on the Web on eBay and
AstroMart
• Can be bought ready to go for astrophotos
for $50.00 or less
• Uses Sony ICX098BQ CCD chip
• Has 640x480 array with 5.6µm pixels
• Works best at 5 to 15 frames per second
Solar System Cameras
Phillips SPC-900NC
• No longer in production but still
available brand new from eBay and
used from eBay and AstroMart
• Cost to make this camera ready for
astrophotos is generally under $75.00
• Uses Sony ICX098BQ CCD chip
• Has 640x480 array with 5.6µm pixels
• Works best at 5 to 15 frames per
second
Solar System Cameras
Celestron NexImage
• Commercially produced imager based
on the Phillips ToUcam design
• Available at major astronomy and
photographic shops as well as on
Amazon.com for under $100.00
• Uses Sony ICX098BQ CCD chip
• Has 640x480 array with 5.6µm pixels
• Works best at 5 to 15 frames per
second
Solar System Cameras
StarShoot Solar System Imager III
• Commercially produced imager using 1.3
megapixel CMOS chip
• Priced at $189.95 at Orion Telescopes
• Comes bundled with MaximDL Essentials
software
• Uses Micron MT9M001 CMOS chip
• Has 1280x1024 array with 5.2µm pixels
• Maximum frame rate of 15 frames per
second
Solar System Cameras
SAC Systems Model 7b Imager
• Commercially produced modified webcam
with Peltier cooling and long exposure
capability
• No longer in production, but available used
on websites like AstroMart for generally
less than $200.00
• Specs vary per production run but all
imagers have 640x480 CCD chips
Solar System Cameras
DV Camcorder
(aka – the camera that you already have)
• Lower TCO by using a camera you already
have
• Conversion for astro use is not permanent
and can cost as little as $30.00
• Fixed lens requires that images be taken
using afocal photography rather than prime
focus photography
Tips for Afocal Photography
• Use an eyepiece with long eye relief
• Couple the end of the camera lens as close as
possible to the eye lens of the telescope
eyepiece
• If possible, set the digital camera at macro mode
rather than infinity
• Use full optical zoom, but do not use digital
zoom
• If possible, use a camera lens with a focal length
longer than the eyepiece focal length
Solar System Cameras
Imaging Source DMK 21AU04.AS
• Commercial camera originally designed for
industrial applications
• monochrome but available in a color model
• Suggested retail price $390.00 but can be
had for less at certain retailers
• Uses Sony ICX098BL CCD chip
• Has 640x480 array with 5.6µm pixels
• Has a maximum frame rate of 60 frames
per second using firewire port, but this USB
model performs better at 30 fps on my
laptop
Solar System Cameras
Luminera SkyNyx 2.0
• Commercially produced camera specifically
for astrophotography, this is the entry level
model for this line
• Monochome and color versions available
• Retail price $995.00
• Uses Sony ICX424 chip
• Has 640x480 array with 7.4µm pixels
• Maximum frame rate is > 100 frames per
second
Solar System Cameras
Dragonfly Express
•
•
•
•
•
•
By Point Grey Research
Industrial firewire camera – Point Grey is
just beginning to cater to the astronomy
market
Monochrome and color versions available
Suggested Retail price is $1195.00
Uses Kodak KAI-0340DM/C CCD chip
Has 640x480 array with 7.4µm pixels
Has maximum frame rate of 350 frames
per second
Software
Image Scale
3777mm efl @ f/18
5846mm efl @ f/25
6342mm efl @ f/23
8416mm efl @ f/24
13,149mm efl @f/40
So – how does this work in
practice?
Image Scale – Prime Focus
Image Scale – Prime Focus
Image Scale – 2X Barlow
Image Scale – 2X Barlow
Hey, wait a minute…
Hey, wait a minute…
• If the line is 72 pixels long at prime focus,
shouldn’t the line be 144 pixels long with
the 2X Barlow?
Hey, wait a minute…
• If the line is 72 pixels long at prime focus,
shouldn’t the line be 144 pixels long with
the 2X Barlow?
• No. The actual magnification of a barlow
is determined by how far the imaging chip
is from the last lens in the barlow.
Hey, wait a minute…
• If the line is 72 pixels long at prime focus,
shouldn’t the line be 144 pixels long with
the 2X Barlow?
• No. The actual magnification of a barlow
is determined by how far the imaging chip
is from the last lens in the barlow.
• This behavior gives us some interesting
options for increasing the image scale in
our Solar system images!
Televue Barlow Magnification
Image Scale – Barlow w/extension
Image Scale – Barlow w/extension
So – what did we get?
• 72 Pixels represents “1X” – baseline
• With the “2X” barlow in place, the line went
to 176 pixels – in actuality, my “2X” barlow
is really a “2.44…X” barlow – an over
achiever to be sure
• Adding 36.76mm of extension to the
optical train took the line to 228 pixels,
giving us a total increase in scale of 3.2X
over the native scale – increase this
extension and you increase the scale!
What’s Next?
•
•
•
•
•
How some easy math provides answers to
questions you need to know:
How big will Jupiter be on *my* telescope?
How long *was* my effective focal length?
What *was* the focal ratio of the system?
How long can I expose Jupiter before the
planet’s rotation causes smearing?
Yes, I will talk about capture and
processing too!