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the short story of
one OCA Members journey into CCD imaging
The following story appeared
in th Sirius Astronomer in December 1999. Repeated here now - just because
I can :-) - Liam Kennedy
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Imagine my dilemma. I have
had my wonderful 10" LX200 for the past 18 months and from
the moment I handed over the money for it I have been dreaming
and planning for the day when I could purchase a CCD imager
as well. I am not someone who makes purchase
decisions of these magnitudes very lightly - Instead I agonize
over every piece of information and advice that I can possibly
obtain about every aspect of the product.
My particular journey
into CCD Imaging actually started out in a very modest and
cost-effective way. With the help of a Sky & Telescope
magazine article I converted a very cheap non-astronomical
CCD unit into a pretty useable system good for planetary and
lunar imaging. I converted a Connectix QuickCam Monochrome
camera by hacking a "somewhat" round hole in the front big
enough to allow me to insert an eyepiece adapter. This
allowed me to directly insert this device directly into the
prime focus of my telescope. I was completely surprised
when after all my amateurish efforts I actually saw an image
appear on my computer screen! You can see some of the results
of this early work on my web site at http://www.thekennedys.net/astronomy.
One of the particularly interesting pieces of work was a 2
hour animation I created one night out at Anza when three
of Jupiter's moons were moving into occultation and transit
at the same time - which you can see at http://www.thekennedys.net/jupiteranimation
.
Even despite the limitations
of the QuickCam (and others in OCA have done some truly remarkable
work - which should be published) I did find that it taught
me a few things which have helped me in moving on to the world
of deep space CCD astronomy. One of the best lessons
I was taught was related to the art of placing and focussing
the image onto the CCD chip. In comparison to the more
costly CCDs getting the image and focussing using the QuickCam
is so easy - mainly because of the very fast image download
times which allow for a very easy and quick visual feedback
mechanism.
So - the QuickCam
was an interesting diversion for a while - but the months
went by - and eventually I just had to turn my attention to
upgrading to a more capable device. Something, which
I could use to image fainter objects than my LX200 and I my
eyes alone, could even see. Like my purchase of the
LX200 - I spent endless hours seeking advice and reading articles
- buying books until I felt I had enough rudimentary knowledge
to make an informed decision. I placed a question on
the Meade User Group List (MAPUG) and also onto the new OCA
forum asking for some final pieces of advice from the experts
out there on what I should do. I received a bunch of
very helpful advice from OCA Members like Dean Jacobsen.
I decided to get an
ST-7 from SBIG - which I purchased from my favorite Astronomy
shop - Oceanside Photo and Telescope http://www.optcorp.com
. Along with the CCD I purchased several other items
including a Zero-Image-Shift focuser (the NGF-S). My
QuickCam experiences (and the advice of from other OCA friends)
had taught me there is far too much movement of the primary
mirror when manually focussing using the standard mechanism
on a telescope like the LX200.
After thoroughly reading
the SBIG Manuals and setting up the CCD and playing around
for a few days in my living room I made a trip up to Anza
on an off-star-party weekend to see first-light with my new
device. I would have gone up on any weekend - but I
was particularly grateful to setup for the first time on an
"off-weekend" so that I could spare my neighboring astronomers
from the inevitable initial tantrums as I tried to figure
out what goes where. In the end I must admit there
were very few points of total frustration. I mainly
just took my time with it all and accepted the fact that I
couldn’t possibly start out being an expert.
On that first night
I managed to take images of the moon, M3, M57 and M17 - and
on the whole I was quite pleased with the results.
M57, taken using 10"LX200 F10
with ST7 ABG, OCA Anza site
June 20th 1999 00:01 PST,
8 x 10 Second Exposures
M13, taken using 10" LX200 F10
with ST7 ABG, OCA Anza site
July 3rd 1999 22:18PST,
8 x 10 Second Exposures
Since then I have
progressed onto my first galaxies with the help of a neighboring
pad owner John. I was totally amazed at the sensitivity
of the ST7 and how easy it was to see the faint smudges of
galaxies (or even multiple Galaxies) with just a few seconds
of exposure in focus mode.
Below you can see
my first ever galaxy – NGC 7331 (along with a few other smudges)..
NGC7331, taken using 10" LX200 F10
with ST7 ABG, OCA Anza site
September 11th 1999 21:44PST,
5 x 20 Second Exposures
Focussing is in many
ways much trickier than I had expected as the higher resolution
of the ST7 results in longer download times than the QuickCam.
I do know that I have
a very long way to go before I can call myself any sort of
an expert in CCD imaging. I also know for certain that
being a member of OCA has allowed me to progress in this hobby
far faster than I could ever have managed on my own.
Check out the latest
images on my site http://www.thekennedys.net/astropics
- you'll certainly find the images have room for improvement.
I have even included some of my best "failures" for
all to see. All comments are appreciated! mailto:lkennedy@ocastronomers.org
Oh woe WAS me! Not
any more!
Liam
Kennedy
OCA
Webmaster
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