Post by nigel on May 11, 2005 5:34:06 GMT -5
How to make compressed gas bullet hits
This method uses the force of compressed air to blast fake blood from a length of tubing. Simple!
What you'll need...
A pump-up insecticide sprayer - Its worth investing in a new one as a used sprayer might have some insecticide in and you don't want to kill yourself off before you get to shoot your movie.
Garden Hose - You probably need about 2 metres which you might be able to chop off your normal house. Failing that getting a good length to cut up is useful as you can experiment with different lengths for different purposes.
Fake Blood - For a whole bunch of recipes try Eejit's Guide to Blood. For the example below we used Cardiff Red.
Gaffer Tape - You would think I have a deal with the company cos I talk about this stuff so much. It is useful though.
Sponge - You'll need to rip it into little pieces so buy a cheap car sponge.
Blu-tak - Y'know the putty type stuff used to stick up posters.
Old Shirt
Step One - Cut approx. a 2 metre length from your garden hose reel. About an inch up from one end you need to make a hole big enough to put your little finger in. This is where the blood will be ejected from. We used a heated screwdriver to melt through the hose as it was pretty tough. Probably not recommended though as it gave off these awful fumes. Best to do it in a well ventilated place so you don't pass out.
Step Two - Bung up the end you have made the extra hole in using Blu-Tak. By forcing the blood to fly out of the extra hole instead of the end of the tube it sprays out rather than jets out.
Step Three - Unscrew the spray nozzle from the insecticide sprayer. Attach the unmodified end of the tube to the empty sprayer. Now to work on your biceps! Give the sprayer about 150 pumps. The first 100 or so should be easy but by the end it should start getting more difficult. All this energy is being stored as pressure and when you push the trigger all the energy will be released at once, blasting the blood out.
Step Four - Gently pour in about 20ml of your fake blood to the modified end of the hose. You may need to thin the blood mixture with water to make it less 'gloopy' (err...that sounds technical). Bung up the side hole with pieces of sponge. Ideally use red sponge as this will fly out when you trigger the sprayer looking like chunks of flesh. Mmm...nice!
Step Five - Make a hole in the back of the shirt and feed the tube over the actor's shoulder and down to the area that is going to be 'shot'. Tape the tube in place at the front with the side hole facing forwards.
MOST IMPORTANT BIT!!!
Have the actor get down on his knees and get an assistant to hold the sprayer as high as possible for 30 seconds. This allows the blood to run down and prime the tube. The blood should now all be in the last part of the tube held back by the bits of sponge.
Step Six - The shirt here has been prepared by scoring with a knife. The side hole of the hose should be lined up with the hole in the shirt. Use gaffer tape on the inside of the shirt to close the shirt up.
Step Seven - Have the assistant who will fire the trigger, out of camera shot on the ground. Here stuntman Stephen demonstrates what the setup would look like if it wasn't concealed underneath the shirt.
When positioning the camera be careful. The force was so powerful on one of the tests we ended up showering the camera operator with blood. If you are straight on get a good distance away and zoom in.
Step Eight - Push the trigger!! Ker-BLAM!! Blood flies everywhere. Gore City
OK, that's probably enough to get this page an 18 certificate! But funnily enough its not what you see that makes the effect so gory. In truth there is probably only one or two frames where you can see a flash of red spray. If you pay attention whilst watching some action movies you'll notice the same thing. Most bullet hits are one frame wonders, barely enough for the eye to register.
So what makes these effects so shocking? Turn the volume down and watch the clips again - not so effective huh? There's two reasons for this :
1) Sound is 80% of the effect - It's the bang, crunch and splat that make the effect work. Most of the clips above had had their sound tweaked (using Adobe Premiere). The original sound for the squib movie has explosions that sound like 'pops', they were lowered as the clip was slowed down and become more effective. The compressed air hit had an extra sound of a slowed down and distorted hand clap added to it to beef up the hit. Finally the compressed air head hit had a gun shot and splat added from a copyright-free sound effects CD (the bizarre 'Totally Gross Sound F/X from Hell'). All of the above methods work to increase the shock value.
2) They need to be in a dramatic context - OK, so we've been talking about how to achieve the effect, but this is wasted if they are overused in a film. Repeat the same images again and again and they lose their potency. By watching these clips to see how they are achieved you probably no longer find them so shocking - you've become desensitized to them. To be effective in a film they have work dramatically - we have to care about the character who gets shot, there needs to be a tension in the air before the gun goes off, or it needs to suprise us by happening when we least expect it. We don't always need to see the hit itself, sometime only the effects of the hit (the spray of blood on the car windshield) or the sound of the gun (whilst cutting to a wideshot of a building) can be just as disturbing. Don't believe me? Seen a Tarantino movie lately?
Finally a word of warning - whatever you are using to make your effects be careful. Your cast and crew's safety is vital. Not only that make sure that everyone around you knows what you are doing. We were shooting a bank siege. There were a couple of police cars and van, extras as an armed response team and our lead actor in the middle of all this toting a pair of handguns. A couple of squibs later and he was lying on the floor in a pool of fake blood. Unfortunately this was so realistic that we later discovered that a member of the public had made a complaint when they discovered it was a film we were shooting. They hadn't entered the building as they believed it was for real!
Big-budget effects at low-budget prices! Now you know how its done. So next time you shoot your video, shoot your actors as well. So to speak.
This method uses the force of compressed air to blast fake blood from a length of tubing. Simple!
What you'll need...
A pump-up insecticide sprayer - Its worth investing in a new one as a used sprayer might have some insecticide in and you don't want to kill yourself off before you get to shoot your movie.
Garden Hose - You probably need about 2 metres which you might be able to chop off your normal house. Failing that getting a good length to cut up is useful as you can experiment with different lengths for different purposes.
Fake Blood - For a whole bunch of recipes try Eejit's Guide to Blood. For the example below we used Cardiff Red.
Gaffer Tape - You would think I have a deal with the company cos I talk about this stuff so much. It is useful though.
Sponge - You'll need to rip it into little pieces so buy a cheap car sponge.
Blu-tak - Y'know the putty type stuff used to stick up posters.
Old Shirt
Step One - Cut approx. a 2 metre length from your garden hose reel. About an inch up from one end you need to make a hole big enough to put your little finger in. This is where the blood will be ejected from. We used a heated screwdriver to melt through the hose as it was pretty tough. Probably not recommended though as it gave off these awful fumes. Best to do it in a well ventilated place so you don't pass out.
Step Two - Bung up the end you have made the extra hole in using Blu-Tak. By forcing the blood to fly out of the extra hole instead of the end of the tube it sprays out rather than jets out.
Step Three - Unscrew the spray nozzle from the insecticide sprayer. Attach the unmodified end of the tube to the empty sprayer. Now to work on your biceps! Give the sprayer about 150 pumps. The first 100 or so should be easy but by the end it should start getting more difficult. All this energy is being stored as pressure and when you push the trigger all the energy will be released at once, blasting the blood out.
Step Four - Gently pour in about 20ml of your fake blood to the modified end of the hose. You may need to thin the blood mixture with water to make it less 'gloopy' (err...that sounds technical). Bung up the side hole with pieces of sponge. Ideally use red sponge as this will fly out when you trigger the sprayer looking like chunks of flesh. Mmm...nice!
Step Five - Make a hole in the back of the shirt and feed the tube over the actor's shoulder and down to the area that is going to be 'shot'. Tape the tube in place at the front with the side hole facing forwards.
MOST IMPORTANT BIT!!!
Have the actor get down on his knees and get an assistant to hold the sprayer as high as possible for 30 seconds. This allows the blood to run down and prime the tube. The blood should now all be in the last part of the tube held back by the bits of sponge.
Step Six - The shirt here has been prepared by scoring with a knife. The side hole of the hose should be lined up with the hole in the shirt. Use gaffer tape on the inside of the shirt to close the shirt up.
Step Seven - Have the assistant who will fire the trigger, out of camera shot on the ground. Here stuntman Stephen demonstrates what the setup would look like if it wasn't concealed underneath the shirt.
When positioning the camera be careful. The force was so powerful on one of the tests we ended up showering the camera operator with blood. If you are straight on get a good distance away and zoom in.
Step Eight - Push the trigger!! Ker-BLAM!! Blood flies everywhere. Gore City
OK, that's probably enough to get this page an 18 certificate! But funnily enough its not what you see that makes the effect so gory. In truth there is probably only one or two frames where you can see a flash of red spray. If you pay attention whilst watching some action movies you'll notice the same thing. Most bullet hits are one frame wonders, barely enough for the eye to register.
So what makes these effects so shocking? Turn the volume down and watch the clips again - not so effective huh? There's two reasons for this :
1) Sound is 80% of the effect - It's the bang, crunch and splat that make the effect work. Most of the clips above had had their sound tweaked (using Adobe Premiere). The original sound for the squib movie has explosions that sound like 'pops', they were lowered as the clip was slowed down and become more effective. The compressed air hit had an extra sound of a slowed down and distorted hand clap added to it to beef up the hit. Finally the compressed air head hit had a gun shot and splat added from a copyright-free sound effects CD (the bizarre 'Totally Gross Sound F/X from Hell'). All of the above methods work to increase the shock value.
2) They need to be in a dramatic context - OK, so we've been talking about how to achieve the effect, but this is wasted if they are overused in a film. Repeat the same images again and again and they lose their potency. By watching these clips to see how they are achieved you probably no longer find them so shocking - you've become desensitized to them. To be effective in a film they have work dramatically - we have to care about the character who gets shot, there needs to be a tension in the air before the gun goes off, or it needs to suprise us by happening when we least expect it. We don't always need to see the hit itself, sometime only the effects of the hit (the spray of blood on the car windshield) or the sound of the gun (whilst cutting to a wideshot of a building) can be just as disturbing. Don't believe me? Seen a Tarantino movie lately?
Finally a word of warning - whatever you are using to make your effects be careful. Your cast and crew's safety is vital. Not only that make sure that everyone around you knows what you are doing. We were shooting a bank siege. There were a couple of police cars and van, extras as an armed response team and our lead actor in the middle of all this toting a pair of handguns. A couple of squibs later and he was lying on the floor in a pool of fake blood. Unfortunately this was so realistic that we later discovered that a member of the public had made a complaint when they discovered it was a film we were shooting. They hadn't entered the building as they believed it was for real!
Big-budget effects at low-budget prices! Now you know how its done. So next time you shoot your video, shoot your actors as well. So to speak.
