Hi, Lesley!
You are correct in that Disney's Photo Pass is a wonderful way for groups to get everyone together in some really terrific photos, and not have to remember that, yes, Mom was there, too. Disney's professional photographers are well-trained to pay attention to the iconic backdrops behind you, such as the stunning Cinderella Castle or the beautiful Tree of Life, and they'll even be happy to take your photo with your own camera, too (making sharing photos even quicker!)
Should you wish to purchase some of the professional photos taken by these photographers, you should really consider pre-ordering either PhotoPass+ or PhotoPass CD, both of which are available at a significant discount if pre-ordered at least 14 days prior to your arrival. With PhotoPass+, you'll not only get
all of the PhotoPass photos taken by photographers in WDW, but you'll
also receive a digital copy of the most popular attraction photos, too. That alone sold me on taking advantage of the pre-order price of $149 (regularly $199) on my last two trips; those attraction shots are always hilarious, yet we never wanted to spend the money on them individually. As part of a package, though, we have even better keepsakes of the entire experience. Take a look at these
special offers for Disney PhotoPass for more information.
Should you wish to purchase only a few of these photos, rather than pre-order a package, you may find that you'll spend a bit less, but for only a few photos. For example, according to allears.net (a great source of unofficial Disney information) recent print pricing included $14.95 for two 4"x6" prints, $12.95 for one 5"x7" print and $16.95 for one 8"x10" print. Add up what you might order and that package cost is clearly a great deal.
Hope that helps, Lesley! Send more questions as you think of them; we love to help!