I thought that there was a way to do this...
I seem to recall reading here--a year or so back--about a method for determing the height in pixels of a sliding field while in preview mode. Perhaps the post was in error; perhaps my tired brain is remembering incorrectly; or perhaps later releases of FileMaker have lost this capability.
But my little experiments to try to achieve such a measurement aren't working.
If someone can remember the method--even if it requires Filemaker 10 to make it happen--please let me know as this trick would save many hours of work in a project that I am working on.