Question about texters

I don't know is this question should be ask here due to it's more about Photoshop then Unity but I did not know where to ask. Sorry in advance if so.

Hello, I'm texting a wall in Photoshop at the moment my UV exported from Maya is a PNG at 2048x2048 (and exported from Photoshop as the same format.

When I open the UV in Photoshop I place my base texture in the project window, I use the transform tool to shrink the image to fit into the UV of the shade of the wall, doing this will then loss quality of the textured image making it pixled.

Exporting the image and then using it in Unity also shows up low rez.

Dose anyone know the best way to re-size a image to fit into the UV but still keep it's quality?

I've attached some image of the issue.

The first image is in Unity the left image is the texture (with no photoshoping) I've just added it to a standard material and played about with the tiling to get the size I'm after (this have no quality loss compared to the original image

The texture on the right is made in Photoshop useing the UV's I've shrunk the image down to fit into the UV shape of the wall and it's really low rez.

http://i64.tinypic.com/334p537.png

The next image is the UV i'm using for the model

http://i68.tinypic.com/dmxo36.png

And the last image is the texture image I'm using

http://i66.tinypic.com/t7jsb7.jpg

Dose anyone know how to fix this? Thank you for your time and I hope you have a great day.