By John Reed

An operator sits in a warm room watching a series of monitors.  One monitor displays a dynamic "star chart" showing where the telescope located upstairs in the observatory is pointed.  Another monitor shows a real-time video image of the brighter stars visible in the telescope.  A third shows an image captured by a CCD camera of a distant galaxy.  The operator pushes a joy-stick and centers a star in the real-time image on a video cross-hair.  He then enters a command on his computer and yet another CCD chip begins guiding on that star automatically.  He enters a second command to begin a CCD exposure of another galaxy.  While this exposure is being taken, he processes the first image on his computer to bring out additional detail in the image not visible before.  It is an image which would have taken almost an hour exposure to obtain using conventional film.  In the years before this hour would have been spent in grueling concentration, manually guiding on a faint star.

Who is this operator and where is he located?  Is he at the top of a mountain at one of the world's largest observatories?  Is he some famous astronomer?  No.  He is an amateur astronomer using amateur equipment at his backyard observatory!

As an engineer, no one is more aware of the changes in technology than I am.  It is a challenge to even keep up with the advent of new products, let alone the technical details of how they work.  Hardly a day goes by when some vendor is not telling me of some new technology
which can be applied toward the betterment of our lives.  Amateur astronomy is no exception to this trend.  In fact it is probably affected more by these changes than many other hobbies.

Computers are at the forefront of this change.  I am typing this newsletter on a "notebook" computer only 8.5"x11" in size which has more computing power than a mainframe which took up the entire floor of an office building twenty years ago.  This computer not only allows me to edit the news letter text, but I can check the calendar, look up names and addresses, do complex math and even transmit the text to Conway for David Reynolds to typeset!  With the addition of "The Sky" program I can easily check to see what's up for a night's observing.  If I install digital position encoders on my telescope I can tell exactly where its pointing on the star chart "The Sky" has drawn.  In fact, Bill Franke of our club has this exact setup with his 3.5" Questar.  So the first monitor discussed above is a reality which I have experienced first hand!  As personal computers get more powerful - and they will -more and more tasks will be possible.

The next quantum leap has to be the CCD (charged coupled device) chip.  This is a small (1/4"xl/4") piece of silicon which has tiny pixels (picture elements) embedded on its surface that collect and counts photons of faint light.  The longer the exposure the more photons!  There is no reciprocity loss as there with film.  A twenty minute exposure using film does not collect twice as much light as a ten minute one.  However, a CCD does.  A CCD's exposure is limited only by the light pollution of the sky and thermal noise.  With a CCD it is possible to photograph an object with an amateur telescope that would have only been available to large observatories a number of years ago.  As of now no one in the Club has a CCD for astrophotography, but I have seen one operate at the Texas Star Party.

Dr.  Myrlas Matthews and his son Douglas of Batesville own an SBIG (Santa Barbara Instruments Group) CCD camera and have used it a great deal.  At the Texas Star Party I watched in fascination as Douglas photographed distant galaxies simply by hitting return to download the image.  If the telescope was improperly positioned a one minute exposure would tell this fact.  If the image wasn't centered properly he simply repositioned the telescope, "dumped" the image and started another exposure.  Once he had a "Keeper" he would simply store it on his hard disk for later processing.  No more wondering if the film is even going to come out, the operator knows instantly what he has.  Many experts say that as CCD costs come down conventional film may go out of use for astrophotography.

Anther spinoff of the CCD technology is automatic guiding.  The CCD is so sensitive that with only about a one second exposure it can pick up 7th and 8th magnitude stars.  If this information is sent to the computer, which in turn sends commands to the drive corrector the human is taken out of the loop.  No more long sessions of manually guiding on faint stars, trying to keep them in an illuminated cross hair, usually bent over in an uncomfortable position while the cold night air slowly freezes his feet.  SBIG currently offers this function as a part of their CCD package.  Probably several others do as well.

Before CCD chips video was recorded using a Vidicon tube.  This device worked well only in bright light Therefore it was unacceptable for use on stars.  However new CCD video cameras are now available which work well in quite low light conditions.  In fact, at prime focus through most telescopes all the major planets and several bright stars show quite well.  Randy Stroud has a CCD video camera and has shown entire groups real time views of the moon and planets on his TV monitor.  Several video camera companies have or will soon come out with a video camera that can make longer "expo-sures" thus allowing more stars to be seen in real time.  This would be excellent for guiding or positioning a telescope as mentioned above.  The prices on this equipment are coming down as they are on all electronics so video astronomy should be on the increase.

Finally, positioning the telescope itself has been possible for several years through the use of computer controlled stepper motors.  These little machines don't not work like a conventional electric motor, but rather move in precise steps.  If 100 step commands are issued from the computer, the motor rotates an exact amount If the computer keeps track of these steps, then the telescope's position can be kept up with by a strict method of computer bookkeeping.  Celestron and several other companies have offered this ability for their equipment.

So the scenario described at the beginning of this article is really possible given enough time and money.  However, the equipment is getting better and better and the cost is becoming less and less.  Soon, an individual amateur or club may be able to do all of these things and more.  Is this a good thing?  I think so.  It would be possible to perform serious astronomy, such as supernova searches or variable star work.  However, some may not want to make work out of their hobby.  I think that this technology offers them some interesting advantages as well.  Even the visual observer would enjoy finding objects effortlessly, making maximum use of a dark sky night.  Does technology add as much frustration as it relieves?  Some would say so, but it is here to stay so we all might want to learn more about it and how it applies to our hobby.