INTRODUCTION TO MICROOBSERVATORY This activity is designed for new users. It will take you through the steps of getting familiar with the MicroObservatory site, learning how to use the telescopes, and basic image processing techniques. It is recommended that you print this out, as you will likely need to refer to the instructions while you conduct the activity. Step One: Enrolling To use the MicroObservatory telescopes, you must become a MicroObservatory Team Member by enrolling through the MicroObservatory web site. Do this by going to the Home Page and clicking on "Enroll," and choosing, "Enroll for the first time." You will be asked for a password to enroll, at which you should type in "motm" (minus the quotes). This stands for MicroObservatory Team Member. Please complete the entire form. DO NOT FORGET THE USERNAME AND PASSWORD YOU CHOOSE ON THIS FORM, AS IT WILL BE REQUIRED EACH TIME YOU TAKE AN IMAGE WITH THE TELESCOPES. We recommend using the same e-mail name and password you use for e-mail. All of the images you take will be identified by your username in the image directory; if it matches your e-mail name, you can easily direct other users to your images. Step Two: Selecting a Telescope Select Telescopes from the Home Page, which brings you to a page through which you must select the MicroObservatory telescope you would like to use. Before making this selection, be sure to check 2 things: 1) Telescope status: The telescope must be ONLINE. If you request an image from a telescope that is not online, your image will not be taken. Depending on the reason why the telescope is offline, your image request may or may not be placed in a queue and taken when the telescope is online. This is not recommended, as it is not always possible to predict when offline telescopes will be online again, and you cannot be guarenteed that your image was placed in the queue. 2) Local weather at the telescope site. The satellite images you link to are updated several times a day so that you may choose the site with the clearest skies. Once you are sure the telescope is online and the skies are clear, select a telescope by clicking on the green circle located on the map that represents the region in which the telescope you want to use is located. Step Three: Requesting Images at the Telescope Control Center You must first enter your username and password, which you selected when you enrolled. When to take an image: When you determine what you would like to take an image of, you must be sure that you set the time when the object will be above the horizon. You can find out by clicking "What's Up" in the MicroObservatory frame. If you have a simulation program such as Voyager or The Sky, you can find this information there as well. Where to point the telescope: You may select an object you would like to take an image of, by highlighting it in the list of objects, if it appears there. If the object is not on the list, you must enter the coordinates, RA (right ascension) and Dec (Declination). This information is in the "What's Up" page for many sky objects, or by using one of the sky simulation programs. You may also choose to enter the coordinates instead of selecting the object from the list, for instructional purposes. Camera Selection, Exposure time, Filter Check the "settings" guide to find out which camera settings are best for the object you wish to take (eg, the Moon works best using the Main camera, with an exposure time at a fraction of a second, grey (ND4) filter, zoom out and default focus). Follow the directions to complete the form on the "Control Telescope" page. Be sure to check the "Settings" guide which lists the suggested settings (camera, exposure times, filter, and focus) for the Moon, Galaxies, Planets, and Nebulae. Step Four: Getting your images You will receive an e-mail message for each image that was taken. To retrieve it, go to "Get Images." Click on your username to see your image. You will see a page that contains your image, along with the information that you input when you requested it. Save your image, or any image, by following the instructions for saving the image as a GIF or FITS file. Explore the other images in this file and also in the Image Archive to get an idea of how various objects appear using the MicroObservatory telescopes. Be sure to save any images you wish to keep, as images in the Main Image Directory are automatically deleted in one week. Step Five: Image processing Using one of the Image Processing programs you downloaded, or a different one that you have selected on your own, you may start by opening one of your saved images in the image processing program. Launch the program, and then open your image. To use NIH Image with MicroObservatory Images, you may need to first convert your image into TIFF format (if your version of NIH does not have FITS capability). You can open your FITS or GIF image in Graphic Converter, and save it as a TIFF file. You may also use Graphic Converter for image processing, but its functions are more limited those in NIH. There is a lot more information in a typical image than meets the eye at first. To bring out the fine details, you must PROCESS YOUR IMAGE. Following is a brief descriptionof the kinds of processing that may be useful in your activities (this information can also be found in the MicroObservatory Online Users' Guide. ADJUSTING CONTRAST AND BRIGHTNESS. This is the simplest processing you can do. It is very useful for faint and low-contrast objects like galaxies or nebula. BACKGROUND SPECKS. Some (or many) of the little white dots in your image are NOT stars: If they are a single pixel ("picture element") wide, they are likely to be background noise, called "hot pixels". This noise comes from the light-sensing electronic chip itself and is caused by heat, cosmic rays and other factors. You can eliminate this in programs like Adobe Photoshop that allow you to remove "dust" from photographs. BACKGROUND NOISE. If you use the opaque filter and try to take a picture, you will NOT get a completely black image. That's because the telescope's light-sensing chip itself produces electronic "noise" that is interpreted as faint light. By SUBTRACTING OUT this noise from your image, you can bring out faint details. To do this, you need to use an image-processing program that allows you to subtract one image from another, that is, to subtract the "dark field" image taken with an opaque filter from the image you want to enhance. (Both images must have been taken with the same exposure time.) You may wish to look for the image processing sections of the activities posted to get some practice using various image processing techniques. Step Six: Implement your MicroObservatory Skills The next step once you have become familiar with taking images, saving them, and opening them in an image processing program, is to apply them to a MicroObservatory activity (see the Activities Page, or develop one of your own). You may use images you have taken, or take images from the directory or image archive that suit your needs. Let other participants know your questions, problems, advice by posting a description of your experience learning to use MicroObservatory on the online Bulletin Board, in the Workshop 98 folder. Good luck! Activities Page |