So, you have a computerized GO TO mounting and a CCD camera and want to discover supernovae. What software is available to help you to control the telescope and to check the images? The most popular telescope control solution is that provided by Software Bisque; the same team developed the Paramount mountings to do full justice to their astronomy software. They offer what is arguably the best planetarium package for the serious amateur astronomer, namely, The Sky.
The Sky has always been the planetarium package that advanced amateur astronomers have regarded as "the gold standard." It has never been an inexpensive package, although you can now buy it in cut down "Serious Astronomer" and "Student" editions. The Sky is probably the only package here that can justify the term professional as it is used in thousands of advanced amateur and professional observatories to control telescopes that are involved in real science. This is a planetarium package that leaves nothing scientific out: new discoveries are seamlessly uploaded from the Web. All the scientific data you could ever want is here, if your aim is to explore the night sky. Unlike some competing packages, you will not get dozens of animated tours and you will not feel like you are in a spaceship. The current version 6 is much prettier than version 5 and The Sky 6 display combines beauty and science perfectly. This is the package that the serious amateur astronomer will want to control his or her telescope with total confidence. It may not be quite as intuitive to use as, say, a package like Project Pluto's Guide 8.0, and it is a lot more expensive, but for such a powerful piece of software it is quite easy to master. Where The Sky 6 really excels for supernova patrolling is when it is combined with Software Bisque's other packages CCDSoft (a CCD camera/image processing program) and Orchestrate (a scripting program for automated supernova patrols, etc). All three packages running on one PC are shown in in Figure 9.4. A fourth package, T-Point, provides sophisticated tracking and pointing refinement software for your telescope so that the mount can learn to correct pointing errors.
Efficiently integrating a planetarium package, which controls your telescope, with a CCD camera package, which takes the images, is essential for automated supernova patrolling. If exposures of 30 to 60 seconds are enough to record faint supernovae, the last thing you want to be doing is switching between planetarium and CCD windows on your PC and spending 30 seconds per image just battling with the mouse-clicking activity! Supernova patrolling is carried out at night,when most people are flagging anyway and you want to have the whole process automated. Battling with a PC, moving to different galaxies, and then switching to control the CCD software can be rather tedious after a dozen galaxy images have been taken, never mind a thousand! Obviously some kind of list of commands is required to instruct the telescope to go to another galaxy and then instruct the camera to take an exposure of a certain length and continue this activity for hundreds of galaxies. In the case of The Sky software suite, this is carried out by the Orchestrate Scripting Package (see Figure 9.5), which, as its name suggests, h iE « ® 0) PC 3
orchestrates the operation of the two packages, CCDSoft and The Sky such that when telescope slewing activity stops, an exposure is started, and when the exposure stops, the next slew commences. All this activity takes place without any intervention from the astronomer, who can just sit back and watch the images downloading. In a cluster of bright galaxies, the images can be quite mesmerizing as they download and are automatically saved.
For those observers familiar with The Sky package, enabling Orchestrate simply involves the use of four software packages that already come supplied when you purchase Software Bisque's Paramount, namely, The Sky, CCDSoft, Observatory,and Orchestrate. The usual procedure is simply to start The Sky, power up/initialize the telescope mount, and establish contact between your PC and the telescope mount. CCDSoft should then be used to establish a communication link with the CCD camera. At this point, I usually run the small Observatory package and simply select "File-New". Then I run Orchestrate, go to "Connections" and verify connections to The Sky, the telescope, the camera, and the filter wheel that were already specified when The Sky and CCD Soft were initially set up. A "script file" you previously prepared can then be started once you are 100% happy that everything is working. It is advisable to make CCDSoft the active window at these times (i.e., click on the CCDSoft window to bring it to the front while Orchestrate is running). If all is well, both CCDSoft and The Sky produce little "server" windows that listen out for the Orchestrate controls.
Of course, anyone familiar with software will be well aware that things are often not that simple, and different PCs, different software versions, and driver problems can leave you banging your head against a brick wall! The best solution in all these matters is to join a user group (mostly found on Yahoo!) to help with these issues. Two heads are better than one and two hundred are far better, especially if the hardware/software designers are on the user group. In this instance, the two most relevant user groups are http://groups.yahoo.com/group/paramount/ and http:// groups.yahoo.com/group/SBIG/, both of which have regular discussions of technical hardware and software queries affecting the Paramount or SBIG CCD cameras. But these are just two examples, and it is obviously best to join the user groups relevant to your particular hardware. One problem that is occasionally reported with the CCDSoft-The Sky-Orchestrate trio is that if a problem locks the camera up (e.g., it may become very damp after months in the observatory, or the USB extender might have become very damp), CCDSoft can completely freeze and cannot be shut down, even with the Windows Task Manager. This sometimes happens when the camera cooling is instigated. In such situations, it is best to bring everything indoors and dry it out, replace the camera's silica gel dessicant, check all the connectors, and then try again the next night. If severe incompatibility problems exist with an SBIG camera, try running SBIG's CCDOPS package alongside The Sky, but without Orchestrate. This will make a fully automated system impossible, but it will at least make your remote control telescope usable again.
The most typical format for an Orchestrate supernova patrol script is as follows:
ImageThenSlewTo 60.0 NGC4736
60.0 NGC5055 5
Essentially, this uses commands that The Sky translates into slew commands for the Paramount mounting (or any other compliant mounting) and galaxy designations understood by The Sky, which it converts into coordinate positions used by The Sky. In addition, commands to the CCD camera and their exposure duration in seconds are used, too. So, the example above simply says that the telescope must first slew to the galaxy NGC 5033 and wait 5 seconds for the tracking to settle down after the slew. Then a 60-second exposure is taken before slewing to the next galaxy (e.g., NGC 4736), and so on. While this is happening, the patroller simply watches as CCDSoft (set to autosave) saves the galaxy images to the hard disk.
Of course, few amateur astronomers can afford a Paramount mounting. At the time of writing, the ME cost $12,500. However, it is ultrareliable and will track for at least 2 minutes with no perceptible tracking error. However, the software combination of The Sky, CCDSoft, and Orchestrate will work on any modern mounting, like an LX200 or an RCX400, for example. The difference is that, after a million slews, the Paramount will still be working and slewing to arc-minute precision, whereas lesser GO TO mounts will be on their 20th set of gearboxes and will not put the galaxy in the center of the chip.
Other software packages can be used to control telescopes, too. Project Pluto's Guide 8.0 can do it, as can SkyMap Pro and the higher specification and beautiful Starry Night programs. The difference with The Sky is that it specifically caters for robotic operation and unattended patrolling as it integrates the telescope and camera control with the Orchestrate target script.
It has often been said that patrolling for supernovae is not difficult, and that is very true. In essence, galaxies are being imaged using a modern telescope's GO TO facility and the supersensitivity of modern CCD cameras. The advent of microprocessor telescope control, planetarium software, and affordable CCD cameras has placed the backyard amateur in a more powerful position than any professional observatory prior to the 1980s. The research of thousands of electronics engineers and scientists and the power of mass production has meant we don't have to do the tricky part (i.e., building the equipment): it has all been done for us. However,while taking hundreds of galaxy images is not difficult, checking them still is. This is the part of the process that separates the men from the boys, or, rather, the obsessed patroller from the normal, sane individual. For most people, the thought of searching through 5,000 images manually, in a few days, looking for a new speck of light, is horrendous. It all depends how badly you crave that success and that fame. As with any aspect of life, if you want to achieve something extraordinary, you have to be prepared to endure more misery than the vast proportion of other people. You literally have to be obsessed with the idea of astronomical discovery. Unlike in many other areas of life where a huge obsessive effort is involved (e.g., outstanding athletes, tennis players, and footballers), there is no financial reward at all. You spend thousands of dollars on your telescope and your CCD camera and you almost kill yourself checking the images. But all you get as a reward is one discovery,which the vast proportion of people in the world will never know or care about. So,by normal standards, being barking mad helps in supernova patrolling! If a flawless system of checking images was available, then more people would have a go at this unusual sport. But then everyone would be discovering supernovae and it would not be so prestigious amongst the amateur community.
So, if the nightmare part is checking the pictures, what software techniques do amateurs use to inspect their galaxy images?
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