Well if we take a look at the journal entry it's a bit hard because one of those polaroids is of Rachel, and we know that Max didn't take that specific photo.

And on the more specific character pages?file=Mark_Entry.png) we actually see the same photo used. And, well, Polaroids don't really do that, as its a singular, special photo.

Additionally, for someone that likes to take selfies, she doesn't really appear to have a selfie pose for her own entry.

I mean, hate to say it, but I find it as sort of a 'plot hole' :|. It's more an artistic continuity choice by DONTNOD to make everything Max touches polaroid looking, but it's hard to imagine her really up and asking for a photo of some of these people. Nathan is one thing—at the minimum, they share a class together—but asking total stranger like Frank? Nah.

The only 'realistic' sounding solution i'd have is that Max printed these out from images from the web and made fake polaroid borders to put in her journal to keep it consistent along with her real photos.