I wish there were some documentation on this since virtually everyone has difficulty with plate solving. However, it is worth some time looking at the ToolTips in each of the parameter entry boxes to understand how to optimize the process. There are two steps to plate solving, extracting stars from your image, then matching the extracted stars to the library images. The extraction of stars is done using a program called SExtractor. There is some documentation on SExtractor on the web mostly useful for developers but it is helpful to look at to get a better ideas of what the program is doing. Basically, you select parameters to detect stars above a brightness and size value. You don't want to detect noise as stars nor do you want to select every star in your image, so there are parameters to filter out the dimmer stars and ones that are not round. One SExtractor has done its job you have to prepare the extracted image. For a telescopic image you want to limit the number of stars you pass to the plate solver to 50-100 or so from an initial selection of 500-1000. Too many stars and the plate comparison will take too long, too few and the plate comparison will not yield a result. I think the SmallScaleSolving works pretty well for starters. In my experience it is having too many stars that is the issue rather than not enough, at least for those of us who are working at a FOV of a degree or so.

Read More...