In Pulse there are spirits visible on video and surveillance systems that if I remember right aren't otherwise seen.  (At least the original - haven't seen the US remake.)  This idea of "ghosts in the machine" is common in many recent J-horror films; others have pointed out The Ring but also One Missed Call (again with a US remake) and to lesser extents Juon or Gozu.

Don't know if you want only supernatural occurances but in Predator 2 some of the characters watch an otherwise invisible (or at least almost-invisible) Predator on thermal imaging video.  

Characters in They Live use special glasses to reveal that otherwise normal looking people are actually invading creatures (what J. Hoberman called an EC Comics adaptation of Society of the Spectacle). 

And to go a bit off topic, MR James' story "The Mezzotint" doesn't seem to have been filmed but was a clear inspiration for the Spielberg segment of the Night Gallery pilot.  In this a reproduced image reveals an event in the past - one interesting part is that there are two supernatural events, one past and one present. 

>>>> Dorothee Birke <[log in to unmask]> 1/16/2009 7:39 AM >>>
>Dear list members,
>This is a question for horror film buffs: we are
>currently trying to compile a corpus of horror films in which
>photography is used in order to show things that are invisible to the
>naked eye. Examples would be The Omen, in which smudges on photographs
>foreshadow the deaths of the people in the picture, or Shutter, in
>which photos reveal the presence of a ghost.
>Can anybody think of horror films featuring photographs or
>photographers? We would greatly appreciate your help!
>With many thanks in advance and best wishes
>Dorothee and Michael
>PS: Other films that already came to mind were Ring, The Shining and
>The Asphyx.

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