Specify Sharing to ATV?

I have several ATV's around the house. I love them!

Recently I bought a TV to use as a picture frame and created a specific album in Aperture just for that TV. Instead of having all my albums show up on this one ATV, and I have many of them, can I specify which ATV's see what albums I want only in the photo album list or do they all list the albums that I specify in iTunes.

I rememebr back when the ATV's hard HDD in them, the old white ones, this could be done, but I dont see how in the new black ones.

Any help would be great.

And while I am here, is there a way of increasiong the time per lside past 20 secs. I would like to show a photo for at least a minute.

I know I can make a slideshow in Aperture and then export it as a movie, but it takes forever, takes up a lot of memory and once its converted to a movie it cannot be changed.