You can plot how ever many points you like, but there are only so many pixels for the graph to display the data. For example, if a plot area is 400x300 pixels, then there are 12000 possible dots that can be drawn in that area. If I plot 15000 points, obviously there is no way to display every point. The way graphics programs calculate this is called decimating the data. They look at the data points and the available display area and reduce the data to what can be displayed with the given pixels. If you are seeing a more accurate graph in Excel, it is most likely because the graph is just larger so it has more pixels to work with, or the line styles (thickness, etc.) are different and limiting the display.
Best Regards,
Chris Matthews
Measurement Studio Suppor
t Manager
