User Tools

Site Tools





Reference Manual



Tutorial 6. Plate solving

Many function in CCDciel rely on plate solving so it is important this is correctly set.

If not already done install a plate solving software now.

Because we want the solving time to be just a few seconds we must help the solver software by giving the most accurate information about the image to prevent a blind solving that can long for many minutes.
But wrong information is even worst, in most case it make the solving to fail.

The important points to check in the configuration are:

  • The camera pixel size in microns in the camera options. It is important to check the driver return the correct size, if not you can override the value.
  • The telescope focal length in millimeter in the astrometry options. This must be the effective focal length taking account for any corrector or focal reducer. Do not trust any label on the equipment, the best way to get the real focal length is to do a blind plate solving, look at the result for “Pixel scale” and use the formula:
    Focal_Length = 206.265 * Pixel_Size / Pixel_Scale.
  • The telescope must return good enough coordinates to use as the starting point. The astrometry options “Maximum search radius” must be large enough for any error in the initial position.

Then select the software to use and set any of it's specific options.

When all is ready take a preview image that show enough stars, right click and select Resolve.
Wait until it complete, in case of success it show a message with information about the image position and size.
The solved image is loaded in the viewer, an arrow indicate the direction of North and East and moving the mouse over the image show the RA/DEC coordinates.

In case of error you can right click and select View last resolver log.
The content depend on the selected software, some are very verbose but with other you just get the command line used by CCDciel.
This command line let you try the solve command in a terminal window out of CCDciel to check what is wrong.

When your images are reliably solved you can look at the next configuration tab, Slew. This set additional options to automatically position the telescope with a given precision.

Next tutorial >>

en/documentation/plate_solving.txt · Last modified: 2019/11/06 11:18 by pch