Photo Stream & Camera Roll using double memory?
I have a 16gb new iPad. I've noticed that since taking some home movies using the video camera (total of about 25 minutes) my available internal storage has dropped quite a bit along with my availble iCloud storage. I also noticed that all photos and videos are duplicated between the Photo Steam and Camera Roll. I'm not sure I've really figured out the difference between these two and whether I need them both. If I understand correctly, Photo Stream is there to work with iCloud to backup and also push stuff to other devices (but that feature has a 30day/1,000 photo limit)? On the other hand, the Camera Roll is permanent (although it also backs up to iCloud, depending on your settings)? I also understand that Photo Stream data doesn't eat into the free 5gb on iCloud, but Camera Roll does.
So, my questions are:
1. With respect to the internal storage on the iPad itself, am I losing twice as much memory for each photo/video that is in my Cameral Roll and also on the Photo Stream?
2. It doesn't seem to make sense that I have iCloud backing up my Camera Roll (which eats iCloud storage) if the same stuff is backed up on Photo Stream (without using iCloud storage) - I assume the only reason to continue allowing it to back up the Camera Roll is that the Photo Stream backup has limits? In other words, if I don't backup the Camera Roll and my iPad craps out on me, then my iCloud restore won't inlcude any photos or videos taken more than 30 days ago?
iPad (3rd generation) Wi-Fi