It is all tied into your Disney My Experience account. If you are staying at a Disney resort, you will get a Magic Band included that can be used for photo opportunities in the park amongst other things. If you are not, you can still purchase a magic band and link it to your account for a similar photo experience.
I believe they keep all photos a minimum of a month or two
They can store it to your magic band as well for purchase later.
They have a memory makers package that you can have any of their photographers take photos and you can download them all.
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