Marc,

Check out this picture of a SCROG grow. Notice that only the buds come through the screen (after training of course) this gives the buds the maximum light.

http://www.overgrow.com/edge/gallery...ScrOG--21-.jpg

Go to Overgrow.com (and other boards) and do a search for scrog to learn more about this technique. It is used to improve/maximize the yield per square foot of growing area as well as the yield per watts/lumens of light available.

The pic at the link uses a home made screen but the easiest/best is to use "chicken wire/poultry netting" for the screen. Do some research on the boards and you will be pleasently surprised as I was.

My next grow will try the "Vertical SCROG" methodology. Harder to find info on that one but well worth the effort.

Hope this helps,
Max Blast