The first photographs could not stop. Their silver stayed sensitive, so every look in daylight kept printing them, until the picture was one even brown. Herschel's hypo, in 1839, made the first print that could be looked at and keep. This one is not fixed yet. Looking at it is using it up.
press and hold to shade it with your hand · F or “fix it” to keep it as it is now · space or “new print” to start again
unfixed · 0:00 in the light · nothing lost yet