Seamless image tiles

[kektex]

Hello,
I`ve been trying to get 4 images to blend in seamlessly with photoshop using the gradient tool but I cannot get it to work.
The image is this one http://www.sarliasociados.com/img/homeheader.jpg
How can I get the 4 images to blend in seamlessly using photoshop (or some other tool) ?
Thanks!

 

[Cooper]

You could try using the smudge tool. That may work.
If you want to use a gradient blend, you'll need to use the reflected gradient tool. Click Gradient and on the top tool bar, click the icon which looks like this:

Hope some of that was useful