Most events uses lasers and fog to create some light effects, and they can really create some interesting photos or videos. Unfortunately, they can also permanently damage your camera.
When I was starting with photography, I was asked to make some videos and photos of an event. The camera which was doing the filming was pointing at the stage, and my other camera was with me to take some photos. It was my first experience with photographing low-lit locations and with fog and lasers too. The good part is that I've learned quite a lot about how to shoot in such scenarios since, but the camera that was filming was on a tripod, and it was stationary for the whole time, with a wide angle lens to record the entire stage. Thankfully, the low magnification helped minimize the damage.
So, after the event, I've packed back everything and went back home, and to my sad surprise, there was something very strange on the footage, from the middle towards the end. There were some odd, pinkish spots that didn't look like dust spots, but in fact were the dead pixels on that part of the sensor. The laser projector was pointing towards the crowd (literally towards the crowd watching, the light beam moving around, but every now and then, it could reach people's eyes and my camera too). And these dead pixels shows on every photo that I shoot with this camera now, just like you can see on this image, where I've photographed a piece of paper and left it completely out of focus, so the only thing in the photo is the dead pixels.
It's annoying, but I still can use this particular camera, I just have to retouch the dots, but it could've been worse. I saw some people that had worse cases of dead pixels that made it not impossible but impractical to retouch every single photo due to the amount of damage to their sensors, which resulted in having to replace them. I the camera is used only for video, I don't think it's possible to remove them (depending on the amount of damage).
If you want to avoid this kind of problem, before setting your camera on a tripod to be stationary for the entire time (like me), be sure to check where the projectors are and where they are pointing.
Lead image courtesy of kpr2 via Pixabay, used under Creative Commons.