The Binding of Isaac: Repentance - The Easiest Way to Unlock The Planetarium
The Binding of Isaac: Repentance Tainted Characters Guide | The Binding of Isaac: Repentance
The Ten Best Trinkets in "The Binding of Isaac: Rebirth" - LevelSkip
The Binding of Isaac: Repentance |OT| One last run into the unknown depths below OT | Page 28 | ResetEra
Apparently gulping the faded Polaroid makes it unable to open the door in depths which I guess makes sense since you can't put it in the door if you swallowed it :
Faded Polaroid Stats : r/bindingofisaac
Everything To Guppy: Episode 669: Faded Polaroid on Apple Podcasts
Binding of Isaac: Rebirth Item Ideas 2 by A-Ithyphallophobiac on DeviantArt