While using the graphics debugging tool in VS 2013 is it possible to choose and step-by-step debug a concrete pixel in the pixel shader? No matter which pixel I select using the crosshair in the captured frame, the pixel which is analyzed while stepping in the pixel shader is always the same (the interpolated texture coordinates do not change for example). Thanks.

Have a look at this demo of the Visual Studio Graphics Diagnostic tool:

Improvements to Visual Studio Graphics Diagnostics

And here is a blog post about the Graphics Diagnositc tools that maybe can help you:

Graphic Diagnostics in Visual Studio 2013

Or you can directly read the MSDN documentation about the shader debugger:

HLSL-Debugger

Thanks I will definitely check those out. I have also realized that my VS 2013 only has Update 2 applied so I'm downloading 4 now, that will probably help too :).