Pixel Perfect Camera and UI?

Hi
I want to make a pixel game. I use the unity pixel perfect camera with crop frame.
So I have the black borders. Now I want to make an UI but i have the problem that the UI orientate on the real image borders and not at the black borders. How can I make an UI that works together with the pixel perfect camera?

 

I had the same problem, but threw away the idea of using the canvas for the same reason. So I opted for another solution and now I have my user interface attached to my camera and I detect the buttons pressed with a raycast.

 

Instead of drawing the UI to the screen in the traditional fashion, use a separate camera to draw it to a RenderTexture.

 

the idea to solve is over render texture is nice.
But i dont worked with render textures is there somewhere a god tutorial how to do such an ui?

 

good idea. but what about performance in mobile devices for example?.... Is using 2 cameras efficient?...

 

This salution sounds good but how do you solve different resolutions?

 

in my case, i let that "2D Pixel Perfect" do the job with the "Crop Frame"and "stretch fill" option enabled.