When I connect an iPad to a Mac, which photos are available for import?

Question

I seem to have created an ever-growing, self-multiplying population of photos shared between my Mac, my iPad, my iPhone, and iCloud!
I'm trying to clear everything up and start from scratch, but one thing in particular is bothering me. I connect my iPad with a USB cable to my Mac, open iPhoto on the Mac, and look at the iPad under Devices. It is showing me that there are 1331 photos, of which 724 have yet to be imported. Yet the vast majority of these photos are actually already in iPhoto on the Mac.
What I'd like to know — and I'm finding impossible to work out — is: exactly what photos on the iPad am I seeing? Obviously not just the photos in the Camera Roll, which if I look on the iPad contains 284. Does it include the contents of "All Imported" that shows up under Albums on the iPad, and contains 1046 photos? This gives the correct total number that is showing in iPhoto (well it comes to 1330 instead of 1331). But I can see some pics in iPhoto, in the iPad device window, that do not seem to be in the Camera Roll or All Imported on the iPad itself.
It's all very confusing, and I can find no documentation about this question. Anyone any ideas?

Answer 1

There is not much documentation on this.
The iPad User Guide (http://manuals.info.apple.com/MANUALS/1000/MA1595/en_US/ipad_user_guide.pdf) states, that the photos you imported from a camera to your iPad can be imported from the iPad by connecting it via USB to your computer. iPhoto or Adobe Elements can import them.
Does it include the contents of "All Imported" that shows up under Albums on the iPad, and contains 1046 photos?
So yes, the "All imported " events will be included.
But I can see some pics in iPhoto, in the iPad device window, that do not seem to be in the Camera Roll or All Imported on the iPad itself.
Have you photos hidden on your iPad (in iPhoto)?