Making High Res Pictures of my Application

I know in other Engines it is possible to start the Applikation in every Resolution i want, and it is also possible to save to picture of the Camera in a Image format want.

Because i want to print some scrrenshots of my Application, is this also possible in Unity?

And if so, how do i change the resolution beside the settings at the Start window. Or is it even possible to save a screenshot in another resolution as the Application runs?

You would use SetResolution to set the resolution:

http://unity3d.com/support/documentation/ScriptReference/Screen.SetResolution.html

And CaptureScreenshot to grab a screenshot:

http://unity3d.com/support/documentation/ScriptReference/Application.CaptureScreenshot.html

If you have unity pro, you can alternatively use a RenderTexture at the size you want and use Texture2D.ReadPixels to get the image into a Texture2D, then EncodeToPNG to get the bytes from that - how you write that to disk is up to you (though probably System.IO.File.WriteAllBytes)

I also found this topic on the forum:

http://forum.unity3d.com/viewtopic.php?t=6969

Taking a complete screenshot in 8192x8192 gives me a very strange camera few. Also the render-scene-with-multiple-screenshots way is very unhandy since you have to stick the seperate shots together.

Someone found a complete solution so far?

Trying again… https://trajano.net/2017/06/creating-a-high-resolution-camera-shot-on-unity/

var width = 3840;
var height = 2160;
var rt = RenderTexture.GetTemporary(width, height, 24, 
  RenderTextureFormat.ARGB32, RenderTextureReadWrite.sRGB, antialias);
var tex = new Texture2D(rt.width, rt.height, TextureFormat.ARGB32, false);

RenderTexture.active = rt;
Camera.main.targetTexture = rt;
Camera.main.Render();
tex.ReadPixels(new Rect(0f, 0f, tex.width, tex.height), 0, 0);

var data = targetTexture2D.EncodeToPNG();
File.WriteAllBytes("camera shot.png", data);

Camera.main.targetTexture = null;
RenderTexture.active = null;
RenderTexture.ReleaseTemporary(rt);