Background Images lose quality when sized down.

Hello Everyone,

I am not real sure exactly what the best thread for this question is, but this is my best guess.

I am following through the video tutorial on CGcookie.com By Jonathan Williamson “Modeling the Female Body”.

He insert a series of background images, and sized them down to an appropriate size. I got the same pictures he did, I insert them exactly as he did, and sized them exactly as he did. The problem is his images still seem very clear, and mine have lost a great deal of clarity after I resized them.

Could anyone tell me what might be happening, and how I can fix it.

That is a link to the tutorial, after about 3:00 you can see his images a resized, but still very clear.

Any help would be greatly appreciated.
Davin