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Emulate muzzle flash on set? (leds?)


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This is my first post so go easy on me haha.

 

I'm shooting a scene that includes some long takes in very low light inside. Were mostly lighting with practicals and shooting with a wide lens on an F5 with a DJI Ronin. There are some gunshots that are shown on screen and I'd like to at least get a bit of light to flash when the actors press the trigger. Can anyone suggest a way to get a light (preferably on the end of the gun) to flash when the actor presses the trigger?

 

I've searched this site, but the suggestions don't really work for my scenario.

 

It's a thesis for a filmschool project, so using blanks indoors obviously isn't an option

 

 

 

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I've never seen or heard of anyone managing to achieve something like that before. Firearms muzzle flashes are a pyrotechnic special effect, and you can get them from firing blanks in operational guns, or by using CGI flashes that are added in post (but generally look pretty godawful in my experience).

 

To my mind, if you want to shoot a pyrotechnic sfx like muzzle flashes, you've got to put down the cash for an armourer and the necessary permits to allow you to shoot them.

 

I'm not really sure why you'd choose to shoot a gunfight for a thesis project and then not do it properly - because if you don't do it properly, what are you learning/proving?

 

Your only real alternative is to fake it with CGI, and there's plenty of tutorials online that will show you how to do that - though you won't be able to accurately create the lighting effect of the muzzle flashes on the faces and environment surrounding the guns when you do things that way.

Edited by Mark Kenfield
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Thanks Mark. I feel as though I didn't make myself clear enough. The LEDs aren't to make a muzzle flash, but to illuminate the area around so we don't have to have more vfx than the flash itself. Does that make more sense? We just want the area around to see some spill when the gun goes off, (i.e. on hallway walls and the people's faces)

 

Technically it's only a junior thesis. Practice for a thesis, but the directors usually end up pouring in their own money. I'm just the DP, it's not like I chose this gunfight scene, it's what the director I work with chose to write about. Obviously shooting with permits and all would be ideal, but it's not always in budget.

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I did a shot outside and did all the flare and lighting effects in Photoshop. Basically duplicated the frame onto a new layer, brightened it drastically and warmed it up, then figured out where the light from the flare would hit (faces, trees, etc.) and erased everything else out. Since it's only a frame or two per shot, it wasn't too much work, and I think it looked pretty good for low budget stuff. As Mark said, it seems everybody and their brother has an online tutorial for this.

 

This probably won't work for you if you are in a dark environment though. Maybe you could do a wire, tape & rubber band approach by mounting a small photo flash (maybe gelled warm) near the shooter but hidden (maybe even on the shooters arm) and use a slave trigger every time the gun is supposed to fire. That would give you a bright flash in the general area of origin. Just a thought.

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I built a rig for doing this using LED strip and a microcontroller board, so it could be timed to sync with the shutter and avoid flash banding on rolling-shutter cameras, as well as ensuring that the flash was actually visible. The actual light-emitting device was a load of LED strip stuck on a bit of plastic, equivalent to about 20W of LED, which wasn't really bright enough - I've since bought a much more powerful emitter and controller board for it but I don't currently have much use for it, so it's a backburnered project right now.

 

There were two ways of triggering it. Some of our prop guns had electronics in them to trigger the flash via a TV-remote-style infrared communications protocol, and I built a tiny PCB with a microphone to allow things to be triggered from the soft "pop" produced by an airsoft gun, where there wasn't room to include electronics.

 

In bright lighting conditions it doesn't make much difference, but in the dark, I think it's quite effective. This is ungraded, without the flame effect composited in.

 

Dark:

post-29-0-56843900-1412352938_thumb.png

 

Bright:

post-29-0-69789200-1412352948_thumb.png

 

In this case it's infra-red triggered and the emitters are hidden in the mock sight on top of the machine pistol he's holding. Batteries inside, power switched on and off by a reed switch actuated by a magnet on the removable magazine. The cheap trick here is that it's very backlit so it looks like he's being revealed by the muzzle flash.

 

P

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