Hi Daniel,
Can you post the code that you use to export the image in order to replicate the problem. In the case of 3D you can explictitly turn on antialiasing using:
nChartControl1.Settings.JitterMode = JitterMode.Enabled;
nChartControl1.Settings.JitteringSteps = 4;
for 2D the code is:
nChartControl1.Settings.ShapeRenderingMode = ShapeRenderingMode.AntiAlias;
Let us know if the problem persists...
Best Regards,
Nevron Support Team