Gravity drip irrigation?

I'm pretty sure I'm going with this type of watering for my outdoor patch. I like the idea of a constant drip. My only question is do I need some type of pressure regulating part in between where the water falls through and the 1/2 " hose? I'm trying to make it similar to the one in this video


http://www.youtube.com/watch?v=mAPHbARo6ug


I just don't understand the use for all those seperate pieces he's got

I briefly looked at the video, it didnt look very gravity fed to me, all the pipes were lying flat on the ground. All you need is a giant reservoir of water, that is higher then your plants, whether that be a barrel in a tree or a kids pool on a hill. You could find an area of a brook thats higher up then your plants, and theres your reservoir. All you need is some simply cheap old garden hose, set it up to the reservoir and gravity will do the rest. There is these attachments that hook up to the end of hoses and or piping, and they are regulated for so many drips per hour, the hose is placed in the soil near the base of each plant with the dripper at the end of the hose, dripping so much water on it, the one in this photo for instance, drips an average of one gallon of water per hour, but there is all sorts of different size drippers to suit your needs. Hope this helps, happy toking

He used the pex plumbing fittings, and some drip irrigation lines.

You could do it with cheaper stuff.

Put a valve on the main output so you can turn it on, and off.

yeah that does help man. So I don't have to worry about the funnel into the hose regulating the pressure because I can just use those pieces you've shown which I already have. derr lol...would you happen to know if a constant drip would be over-watering?