Edited by Jeff Medkeff
This is truly a cloudy nights project. In the Hoosier state,
it is always cloudy for the last half of October and the first half of November.
I purchased a copy of ATC from Salvo Massaro over a year ago. He can be reached
at salmas@inwind.it and his web site is at http://www.omegalab-atc.com/. You
can download a demo windows version of ATC from this web site. My intent then,
as it is now, was to automate my Meade 12” LX200 Classic Telescope operation
so that I can operate the system over the internet. To implement this goal,
I need a telescope control package, a dome control package, and a network
interface that will allow windows control of one PC from another PC. ATC version
2.0 provides much of the needed software for the telescope. I am writing the
software to run the dome. The dome control will employ a single chip computer
like a Motorola M68HC11 family part. This unit will share a serial port interface
with the PC and the telescope. I am using the package called Virtual Network
Computer, VNC, from AT&T to control one PC from the other.
ATC meets essentially all of my needs for telescope control
software. It drives the LS200 Classic telescope through the serial port on
the computer. ATC uses the telescope database for GOTO control and information
about objects. The telescope driver is proprietary and the software has no
ASCOM capabilities.
Salvo has been very responsive to my needs. There were some
formatting problems because of European vs USA ways of doing things. These
were corrected immediately. The operation of ATC is very intuitive. Across
the top of the screen are a series of blocks that contain parameters entered
for the telescope site and date/time windows. The system shows Local Civil
time as well as Local Sidereal Time. Also shown is the GMT offset. This screen
is shown in the figure below.
Three windows below the header shows the Telescope Info, Motion
and Detection limits and Object Info. The Telescope Info contains pointing
information, Hour Angle, Right Ascension, Declination, Altitude, Azimuth,
and mount type, mode -- Alt/Az vs Polar.
The Settings window contain the limits of pointing range, brightness
of the stars to observe and the range of angular resolution to be observed.
It also lists the field width of the telescope. A subwindow at the bottom
of this window shows the refresh rate of the screen. With the screen refresh
rate of 300 milliseconds you can easily follow the motion of the telescope
as it moves.
The third window in this field contains information on the
object being viewed if it is known. It contains a list of Object, Type, Magnitude,
Size, Hour Angle, Right Ascension, Declination, Altitude, and Azimuth. These
parameters are for the target and not the Telescope pointing. When the telescope
is properly aligned with the target, the corresponding displayed parameters
for the telescope and the object match very closely—perhaps to within
1 or 2 arcseconds all of the time.
Directly below the Telescope window is a small window that contains
the Rise, Transit, and Set times for the object being tracked.
A fourth window below the header is right of the three windows
discussed above. This field contains two functions. The first show the angular
distance between the telescope and the object. This distance is shown both
graphically with two bar graphs and in RA and DEC angles. The only time that
there is information in this window is when the telescope is being moved to
a new object. Any time that the telescope is tracking an object, these values
are all zero.
Below that display is a controller for the focus. Focus is an
open loop control that drives an electric focus motor through the LX200 control
panel. There is no braking capability built into the focus system and no focus
speed adjustment, so focus through this software is primitive at best. It
does display a number that shows the relative position of the focus system.
This number can be reset through this window. Also, the focus motor can be
turned off from the screen.
Directly below the focus controller are two control windows.
One allows control of the tracking frequency. The other controls the slew
rate of the telescope. There is also a reticule control panel that controls
the brightness of an illuminated eyepiece through the LX200 control panel.
An additional window on the left side of the screen permits control of the
reticule illumination.
The lower right hand corner of the of the main screen contains
a slew control center. You can move the telescope in the standard North, East,
South, and West directions. You can set to move in pulses of about ½
second, or continuous. The continuous motion must be stopped once started.
The telescope moves at the rate entered in the slew control panel. Also, in
this subwindow is a button named Center. Activating this button brings up
another panel useful for focussing and centering a target in the telescope
field of view. This operation is discussed below.
The remainder of the screen contains a series of buttons –
37 of them. Any function that you can execute from the classic LX200 hand
controller can be executed from this series of buttons. They are very convenient
and easy to use. You can enter objects listed in Messier, NGC, IC, UGC, Meade
Star Number, several popular Star names, Planet name, SAO and GCVS catalogues.
You can also specify coordinates, RA and DEC of a target. Night Vision turns
off all icons on the computer screen and sets the gray background of the ATC
window to red. Other control buttons on the lower section of the screen allow
changing or setting the site information and so forth.
A new feature added to ATC Version 2.0 is a panel display.
The first panel display is shown below. This display is accessed by clicking
on the >> button right below the refresh rate window on the main display
window. This panel operation brings up the small control panel shown below.
Notice the several tabs at the top of the panel. Each of these tabs bring
up a small window with the control features indicated. You have complete mechanical
control of the telescope from these small panels, but many of the features
found with the buttons at the bottom of the main panel are not available.
This small panel does allows use of your computer screen for other things
such as display of focus images while adjusting focus on the Telescope Control
Focus panel. You can move back to the main panel by depressing the <<
button on the Telescope Control panel. I find the addition of the control
panels to the ATC program welcome.
I have not been able to communicate properly with Salvo in
regard to telescope parking. My understanding of the LX200 parking sequence
should be to slew the telescope to a RA equal to the Local Sidereal Time and
a DEC of zero degrees. Then put the telescope into the Land mode or turn it
off. If it is put into Land mode, it should be automatically returned to normal
sidereal tracking operation when the telescope is turned on. The system automatically
assumes that the telescope is pointing due South, the RA equals the LST, at
zero DEC when it is turned on. Therefore, it should be within a few seconds
of alignment when it is powered up. Alignment then requires only synchronization
with a nearby star. Of course, I am assuming here that the telescope is mounted
on a permanent pier. I do not yet understand what happens with the ATC Parking
and Unparking operations.
The Center button found on the motion control panel of the
main screen brings up the following window. From this window, you can center
the telescope on a particular star in an image. The image can be an active
image recorded from your CCD or it can be a copy of an image saved on the
Windows Clip Board. All of these functions are activated by checking the Settings/Parameters/Maxim-CCD
button. The system then assumes that there is a CCD camera attached and will
allow access to the camera control panels. The camera control panel is accessed
by depressing the CCD button on either the main panel or the Center Panel
below. Here you can set and control all of the major camera parameters. Practical
operation of this window requires MaximDL/CCD, but use of this window is not
essential to the general operation of ATC.
The help screens are an HTML file that contains a complete
help system. There are several places where the language could be clearer
for the English speaking crowd.
Overall, I have been very pleased with the function and ease
of operation of ATC with my system. I have been moving and building a dome
which has played havoc with my observation time. Hopefully, I will be able
to become a more active observer now that I am finishing up my observatory.
I am certain that I will be a more efficient observer when I use the ATC package.
I am especially looking forward to implementing a fully automated Dome that
I can control from the comfort of my study a few hundred feet from the Dome.
Then phase 2 of the project will see an interface to the internet so that
control can be from anywhere in the world. The ATC system will be key to the
implementation of these plans.
I have no relationship with Omega Labs. This review is purely voluntary on
my part.
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