If this is a TableNode, set smaller Diagram.RoundRectFactor in WPF to get smaller corner arcs. Are you referring to the resolution of the arrow image in caption bar? I can't see any difference between the two images.

I hope that helps,
Stoyan

1. If using the RoundRect shape and millimeter units, try setting the following when initializing the diagram:

Shapes.RoundRect.Outline[0] = new RoundRectangleTemplate(0, 0, 100, 100, 3);

This makes the corner radius of all rounded rect shapes 3 millimeters, the same as in WinForms.

2. Is this a static image assigned to the node's Image property, or are you generating the image dynamically?

It seems WPF renders images a bit blurry if they are not at exact integer coordinates in pixels, which would happen in your case when the scale for millimeter unit is applied. You could align nodes to pixels as shown below, the images look better then:

var imgWidth = GraphicsUnit.WpfPoint.Convert(image.PixelWidth, diagram.MeasureUnit);
var imgHeight = GraphicsUnit.WpfPoint.Convert(image.PixelHeight, diagram.MeasureUnit);
node.Resize(imgWidth, imgHeight);

var p = diagram.DocToClient(node.Bounds.Location);
p.X = Math.Round(p.X);
p.Y = Math.Round(p.Y);
p = diagram.ClientToDoc(p);
node.Move(p.X, p.Y); 

I hope that helps,
Stoyan