Blinding Camera Flash

A person uses a camera and takes a photo...and the flash wasn't off. The resulting flash either blinds the unfortunate recipient of said photo or makes him see spots. This can be used as a handy distraction or even as a nasty form of Improvised Weapon. Truth in Television, as anyone who's ever had to take a school photo or have been at an area with a lot of flash photography can attest. Sub-Trope of Blinded by the Light.

Examples of Blinding Camera Flash include:

Film

Accidentally happened in Hoodwinked.
In Toy Story 2 the toys use flashes to stop Stinky Pete from hurting Woody.
At the very beginning of Finding Nemo, just right after capturing Nemo, the scuba diver takes a picture of Nemo's father Marlin, the flash stunning the clownfish and preventing him from going after his son.
Used in Rear Window as a way to stall a killer.
In I Love Your Work, the main character is a Hollywood actor who gets disoriented whenever walking the red carpet by the flashing bulbs. In the end, there is a callback to this as he makes a stand against a line of cops.
In Johnny Dangerously, there's a scene where Johnny gets photographed repeatedly and then promptly walks into the wall he couldn't see anymore.

Literature

Discworld:
- In The Colour of Magic, the Cosmic Horror Bel-Shamharoth is defeated by the flash of Twoflower's iconograph going off.
- Exaggerated by Otto von Chriek ever since his introduction in The Truth. He's a vampire who loves photography. As a result, whenever he takes a flash photo, it results in his demise until blood is poured on his ashes. He's tried a few solutions, but not using the flash hasn't been one of them.
Used as a political dirty trick in "A Bathroom Of Her Own" by Robert A. Heinlein. A political candidate is blinded by an unexpected camera flash, with a second picture being taken a moment later as he tries to recover. The picture from the second camera - showing the candidate looking confused, dazzled and dopey - is then used by his opponents in their attack ads.

Live-Action TV

Happened in Quantum Leap to Sam when a reporter's flashbulb exploded in his face, temporarily blinding him. Since Sam was currently impersonating a blind person, this saved him from being exposed as a sighted impersonator.
In an episode of CSI where the Victim of the Week was a celebrity, Al Robbins, the coroner, caught a paparazzi in the morgue trying to photograph the corpse. He tried to use this to escape...Dr. Robbins was having none of it and tripped him over with his cane before calling security.

Tabletop Games

Paranoia supplement Acute Paranoia, adventure "Me and My Shadow Mark IV". The PCs' mission equipment includes a lightbot named Mikey, who was intended to be a photographer's assistant. If the word "light" is used around him he'll start flashing lights in the unfortunate character's eyes, blinding him.

Theatre

In Christopher Durang's play The Actor's Nightmare, just before the Show Within a Show starts there's an announcement that no flash photography is allowed - and then when George comes out there's immediately a bunch of flash photography, blinding him.

Video Games

Tourists can use this as a weapon in Nethack.
Toejam and Earl in Panic on Funkotron features Hawaiian Shirted Tourists who use their camera flash as a weapon.
The scanner enemies in Half-Life 2 do this if you're looking at them when they photograph you (this is pretty much the only hazard they pose, apart from occasionally giving your position away to a strider).
In Fallout 3, your character being blinded by one on his birthdays as a child is used to transition to the next point of your character's childhood/the tutorial.
The video game Academy of Champions: Soccer has one character use a weaponized camera flash as a special move that blinds other players.
In Eternal Darkness, Peter Jacob (a WWII journalist) has a flash pan with a limited amount of powder which he can use to stun enemies (which is good, since you don't really start off with any particularly powerful weapons in that chapter).
This is one of Frank West's moves in Ultimate Marvel vs. Capcom 3.

Web Comics

As El Goonish Shive put it, "Dude, Like, Sarah Just TOTALLY Flashed Female Justin"

Western Animation

This happens in an episode of The BBC's kids' show Kerwhizz, when contestant Ninki is trying out her new camera on her canine companion Pip, much to his annoyance.
Ed Edd and Eddy had an entire episode revolving around a camera.
Used on The Simpsons as a weapon against crazed robot Itchys and Scratchys at Itchy And Scratchy Land. Flashing them caused their brains to go haywire.
In the "school photo" episode of Doug, there's a Running Gag about people being blinded by the camera and wandering around dizzily.
In one episode of Wacky Races, Muttley photographs Penelope Pitstop during the race. Penelope is blinded so severely by the flash that she has to stop driving momentarily.
Muttley does it again, to Dick Dastardly, in the Dastardly and Muttley in Their Flying Machines episode "Lens a Hand".
In the Donald Duck cartoon "Grand Canyonscope", Donald asks the ranger to photograph him atop his burro. The flash blinds the burro, leaving him stumbling along the steep Grand Canyon trail.
Often used as a Running Gag in Eek! The Cat.
This happens to Zach at the beginning of the Adventures from the Book of Virtues episode "Honesty", when he touches his dad's camera and accidentally breaks it.
In the Goofy cartoon "How to Play Football", a player is blinded by flashbulbs and fumbles the ball. He only scores because no one else can catch the ball, and he eventually stumbles upon it at the goal line.

Real Life

It's the main obvious reason (i.e., ignoring variety of overcomplicated hypotheses) for "no cameras" signs in so many quite innocent public places such as museums. Because when it is not prohibited, you guaranteed to have at least one or two morons blinding everyone around with their precious soapboxes every 10 seconds or so.
- Either that or they'd just rather that you bought your mementos at the gift shop rather than just make your own, a lot of museums rely on fundraising from the shops you know.
- There's also the fact that a split second flash is equal to hours of regular lighting, a significant factor when dealing with antiques.