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Getting Started with Live ControlThis page gives you an overview of how to control a telescope with out live control applet:
What to Do When You Have Control of the Telescope:Once you have control of the telescope there are many things that you can do. However to make the process easy to learn we will first show you some basic features and then we will take an image of one of the Messier objects with the primary camera. Then a few more suggestions and you are on your own to explore the night skies! OK - at this point the applet is started and you should have been notified that you have control of the telescope. Pan/Zoom Window:There should be a yellow box on the SkyMap in the right panel. Click and drag inside the yellow box. The area outlined by the yellow box is displayed in the Pan/Zoom Map that is in the upper left panel. Click and drag on the Pan/Zoom Map and the yellow box will move around in the SkyMap. To zoom in and out click the [Z+] and [Z-] buttons just above the Pan/Zoom Map. You can also experiment with the other buttons above the SkyMap and above the Pan/Zoom Map. These buttons are described next. Display Buttons:The following buttons toggle the display of the respective feature on and off - when a button is highlighted, the feature is on. The buttons are:
Clicking a plus ([+]) or minus ([-]) symbol after a feature causes more or less of the respective feature to be displayed when it is on (for example, more (dim) stars or fewer (dim) stars). The current limit for stars in the star database is magnitude 8 (this will be increased in future). At-Scope Camera:The observatories have a camera pointed at the telescope. During daytime practice sessions you can see your telescope move to your slew commands. Except for observatory 207, at night there is insufficient light to see the telescope. 207 happens to have a low light night camera so if you are using this observatory you can see you telescope slew even at night. To use the At-Scope camera, click "Cameras" menu and then select the At-Scope camera. When the camera window appears, click on [Snap] to get a live image of the telescope that you are controlling. The Spotting Camera:Each telescope is equipped with a wide field of view `spotting camera'. The lower left panel is your `Spotting Camera' display and control panel. Click [Snap] to get a live image from the spotting camera. If it is night time, and the roof is open then you should get a wide field view on the night sky. Whenever there is a spotting camera image being displayed, a red box will appear on the SkyMap on the right. The red box indicates the area of the sky shown by the spotting camera image. If the roof is closed the red box will still be displayed however the spotting camera image will only show the inside of the observatory. The Spotting Camera panel has an "Overlay" button designated by the letters [Ov]. The overlay feature overlays a sky map onto the actual live image of the sky from the spotting camera. If the roof happens to be closed the overlay will still appear against the image of the roof. Hence you can test this feature even during a practice session. With overlay turned on all the other buttons work the same as with the SkyMap and Pan/Zoom map. Adjusting Image Levels:A right-click on any image will produce a context menu. Select "Levels" from the context menu and adjust the black, gray and white arrows to affect the image quality. If you are using the "Levels" control to adjust the spotting camera image, then moving the white arrow to the left will brighten the stars and the sky. Moving the black arrow to the right will darken the sky. If the levels graph shows a single main `bump', you can often see more detail in the image if you position the gray arrow just to the right of this bump. Pointing the Telescope:There are several ways to slew and position your telescope. A simple method is to use the SkyMap or the Pan/Zoom map. For this exercise we will first slew to an approximate position. Then we will select a target at random and slew to the selected target. Finally we will locate and select a Messier object on both the SkyMap and Pan/Zoom map and then do a "GoTo Selected Object". Before starting, if the SkyMap is not visible go to the `Layout' menu and make sure all 3 panels are checked. If you have the At-Scope camera active you may need to move it to see the Pan/Zoom map. Slew to an approximate position:If you right click anywhere on the SkyMap, you will get a context menu. Choose the option "Center Scope Here" - your telescope will slew to the sky position where you right-clicked on the SkyMap. If you have the "Repeat Box" checked on your Spotting Camera or At-Scope camera you will see movement in the camera images as the telescope slews. (This right-click/`Center Scope Here' operation also works in the Spotting Camera and Primary Camera panels). Goto a selected object:Double click anywhere on the SkyMap - the nearest object will be circled in red and a description of the selected object will appear in the top right corner of the SkyMap panel. Now right click anywhere on the SkyMap or Pan/Zoom map - the context menu should appear - choose the option "Center Scope on Selected". Your telescope will slew to the selected object. A status box in the lower left corner tells you when tracking is established on the selected object. Pointing your telescope at a Messier object:
Taking a long exposure:Once your telescope is tracking the object you want to image click on the "Primary Camera" tab next to the "SkyMap" tab. The second line in the Primary Camera panel is where you specify binning, exposure and units (for exposure). The default setting for binning should be 4x4, the default exposure next to it should be 1, the default units next to exposure should be sec (seconds). ("4x4 Binning" means a 4x4 rectangle of CCD pixels (16 pixels) are combined together to form a single image pixel: this means shorter exposure times can be used, but the resulting image is smaller and of lower resolution). Leave the binning at 4x4. Increase the exposure time to 30 seconds (if this is daytime practice then set it to 3 seconds - no point in waiting a long time). Check the spotting camera to make sure there are no clouds to block your picture! If there are clouds you will need to wait for them to pass over. If this is a practice session then proceed since you can only see the inside of the observatory! When you are cloud free, click the Snap button for the Primary Camera (click anyway for practice). There is a status box to indicate what is happening with the camera: there will be an exposure, camera readout (scanning) and image download. You should get a low quality image that we will improve on. After the image downloads you will need to use the "Levels" control to enhance the image. Right click on the image and select "Levels" - you will get a levels histogram. If this was a daytime image then you probably have a completely white image that you cannot do much with. However continue to read the instructions as it explains how to adjust the image levels for when you try a actual observing session. If this was a nighttime image then most likely all the data is positioned to the very left. Move the white arrow on the right all the way left and stopping about 1/2 inch before reaching the data bars, then adjust the gray arrow. Take some time to adjust the arrow positions and improve the image. As this was only a 30 second exposure there is not much data to work with, but you should be able to see the basic image and tell if it is appropriately centered before adding more exposure time. If the object is too far off center, simply right click on the spot that you would like to be at the center and select "Center Here". Wait for "tracking" to appear again on the status line (lower left) and then perform another snap. This next one should be centered where you indicated. OK, lets gather more light from this object by stacking (adding together) a number of exposures. Right click on the image and select "Stacking" - a dialog box should pop up. Note the number of exposures ("nExposures") field, which defaults to 10. If this is a daytime practice session you will only be getting a white overexposed image. However continue with the exercise to get familiar with the stacking controls for when you do your actual observing session. Click continue and the stacking run continues from the exposure you have already taken. Ten 30 second exposures will be taken and each image is added to the previous images as they become available. The result is displayed with each added image. Leave the levels control on the screen and keep adjusting with each update. Once you get an image that you are happy with, you can stop the stacking run, or you can simply let it continue to see how the image changes with more stacking. When the 10 exposures are completed you can click continue to stack even more images. If you click new, then a new stacking run will begin. You can also use the stacking control to view individual images and manually reject images that might have been obstructed by clouds or not suitable for other reasons such as wind vibration on the telescope. Saving an Image:To save your image, right-click on the image and select save. You will have a choice of saving the adjusted image with any level adjustments you may have performed, or saving the unadjusted raw image. You also have a couple of image formats to choose from (png, jpg, etc.). A Few Suggestions:OK! you made it this far and if it is a night time observing session then you should have your first image using Live Remote Control at MyTelescope.com! We will make a few suggestions and you're off on your own exploring the night skies! If you do not have a specific object in mind to image, there are 110 Messier objects on the SkyMap to choose from. We recommend that you stay with 4x4 binning to start since the acquisition times are faster. But when you are ready for more image resolution you can switch the primary camera to 2x2 and double your resolution. But when you do this your exposure will have to be 3 to 4 times as long. This can cause problems, especially with objects close to the horizon as the light will be traveling through more atmosphere (astronomers often time their observing sessions so that the object they are interested in is high in the sky). If you were requesting 30 seconds at 4x4 and you change binning to 2x2 then the system will automatically increase the exposure to 2 minutes (30 seconds x 4). We suggest you put the exposure back down to 30 seconds and use stacking to get the longer exposures. Doing long exposures without stacking increases the likelihood of elongated stars. On occasion we have had near perfect images with exposures up to 30 minutes, but to get good results on a more consistent basis we recommend short exposure times between 30 to 45 seconds and use the stacking feature like before to accumulate more light from the object. By doing this you have the option to examine and accept or reject exposures in a stacking run. This will allow you to select the better images to create the best possible result. A word of caution. If you switch to 1x1 binning then your total exposure time can be quite long. Depending on the object, 1x1 binning could require 40 images or more at 45 seconds each. We recommend that you work with 4x4 or 2x2 binning. Filters:The telescopes are equipped with a filter wheel which allows you to select what filter to take an image with. Filters are used to filter out specific wave lengths of light and are most commonly used to create color images (see next section). Most of the scopes have the following filters:
Color Images:The cameras we are using are mono-chrome - if you would like a color image, it must be created from a set of images (for example, a set with a red, a green and a blue image), each taken with a different color filter in place. If you are experienced at using your own software to put together color images from red, green and blue images, then you can use it by saving each filter image to a file and then running your software. Alternately, we have a utility in the applet to combine red, green and blue images to create a color composite, however, we have not had time yet to make this user friendly and so we can't recommend its use. To create the red, green and blue images, begin by using the "Filter" drop down box in the Primary Camera panel to select first filter to use - red (the default is the blank (no) filter). Note that the exposure times will have to be increased when a filter is in place so we suggest starting with 4x4 binning and that you use stacking and stop when you get a good image. Save the (unadjusted) image to a file, and then do this for the other two filters (green and blue). We would be pleased to see the final result from whatever image processing package you might be using! Congratulations!OK, we hope this was not too complicated! Our beta testers typically said that after the first session they were very familiar with live control. We hope you find the same. There are still more features to discover and we will let you explore them on your own. Hmm... one more tip - if you have a specific RA and Dec you want to point the telescope to, then look under the Tools and Devices menu, select Devices and then select the Scope Positioner. Enter the RA and Dec in the appropriate field and click GoTo. Let us know if you encountered any difficulties. We also like to here your suggestions for improvements. You can email us at . And if you enjoy the live remote control experience at MyTelescope.com, please tell your friends!
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