Answer
3628800
Work Step by Step
The number of possible permutations if r objects are taken from n itself is: nPr = $\frac{n!}{(n-r)!}$
The number of different ways you can arrange the photographs, assuming that the order of the pictures makes a difference to you, is:
10P10 = $\frac{10!}{(10-10)!}$ = 3628800 ways