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"Telescope pointing program. It analyzes a sky image with a few stars, and calculates the coordinates of the image centre.
What for ? In astrophotography, a common problem is putting the object inside the ccd frame. Often we are near the target, we have an image with stars but we don't know in which direction is the object. The author wrote this program as a help in such situations. If we know exactly the coordinates of the image centre, it will be easy to drive the mount to the object.
Another situation where Elbrus is useful is when we are far from the telescope (remote control) and we don't know where is the tube pointing to. In such a 'lost in space' case, we can find our position by doing a search in a wide region such as a spherical ring or even the full sky.
Elbrus is also successfully used for recentering the scope between captures. Each image is analysed and the offset from the reference one is computed. This offset is used by the mount driving program to recenter the mount. This way we can cature images during hours in despite of the drift in the telescope tracking.
Program type: Star locator.
Object: Help in telescope pointing from a captured image.
Strategy: Search in the database, by distances between stars and image orientation.Building the polygon with more sides. This algorithm is very fast and very robust. There are no false solutions with more than 15 sides.
At the program entry: An image with stars. Size of the analized area: from 10x10 to 20x30 arc minutes.
Image types: FITS and BMP
At the program output: Image center coordinates, GSC numbers of the identified stars, main identified astronomical objects, distance to the target, direction to the target.
Working modes: manual and automatic.
Image analyse: The full image or a part of the image.
Search in the database: Search in a 5x5 degrees sky window. Search in a 30x30 degrees sky window. Search in a spherical ring. Search in the full sky. Search in a 2x2 degrees window for any camera angle... and more
Database: The database was built for containing: - the 5 brightest stars in every 15x10 arc minutes sky window. - the pre-calculated (smaller than 18 arc minutes) distances between these stars.
Stars in the database: 8 155 625
Distances in the database: 60 332 797
Size of the database: about 800 MBytes.
There are some 'holes' without stars in the database.
Communication with others programs: Synchronizes by ASCOM with telescopes supporting this protocol, with Cartes du Ciel - Sky Charts by Patrick Chevalley, with COR by Cristóbal García, with PicGoto by Angel Caparrós. The program has a DDE server."