You still want to filter the intake. I just use a short piece of ducting with some filter material. The material is half green and half black. No light gets in but it keeps all the dust and crap out of the tent. If you don't filter you're letting crap into your tent that will end up on your buds.
I have two 4 inch and one six inch vent setup this way. You can see all the crap the filter catches.