Here is a useful tutorial, from another site, which is very handy for architectural rendering and is. The link to the site is at the end of the tutorial. The author breaks down the process of equalizing an image to set up a tillable texture. The author also provides a link to a photoshop action to automate the process.
Tutorial: How to Equalize Textures in Photoshop
Isn’t it a beautiful concept to make textures using DSLR cameras? It is, until you won’t place them on a big surfaces and hit tiling problems like uneven brightness, visible seams, color shifts etc. There are few tricks to deal with these problems though. One of them was recently showed here. It inspired me to write this post and show you how I prepare my textures before I make them tileable.