Is it Seamless?
This Tip will show you how to quickly view tiled tiles in Photoshop to determine if they are trully seamless. I can't tell you how many hours I have spend downloading textures only to find out later they produce nothing but lots of squares!!
 
Can you guess which one of the two tiles is seamless?
 
 
Here's how to test...
 
1.) Open desired tile in Photoshop, then go to Edit > Define Pattern. (When the dialog box appears, hit OK.) This will load the tile into the program.
 
2.) Create a new file. Double the width and height values as that of the tile to be sampled. (The tiles above are 100 X 100 pixels, so I created a new file at 200 X 200 pixels.)
 
3.) Now, go to Edit > Fill. Under Use: select the downward arrow and choose Pattern.
 
 
Under Custom Pattern: select downward arrow to access tile to be tested. Click on tile then hit OK.
 
 
Tile A passes the test, there are no visible seams.
 
 
Tile B fails. If you look closely you will see 4 visible blocks creating image.
 
About the Author - Glenn Schemenauer

Thanks for reading.