How can I make convincing fake blood?
Nothing makes a low-budget movie magical like fake blood, and in most cases, fake blood is like strawberry Pop-Tarts — the more the merrier!
There are different kinds of blood and for each kind, you’ll find that you’ll want different kinds of fake blood. For example, there’s fresh spurty arterial blood, then there’s chunky blood, then there’s dried scabby blood, drinkable-from-a-goblet blood, etc.
For most of the blood we used, we used a combination of corn syrup, red food coloring, and chocolate syrup, mixed in that order until the desired color is reached. Be skimpy on the chocolate — that’s just to add opacity.
Blood made this way, incidentally, is edible, but, unless you want a set full of crazed raving sugar-junkies on your hands, be sparing with the eating-suggestions. Give people healthier things to eat and let them know that at least they don’t have to worry if they get blood in their mouths.
Different textures can be added to make different textured blood. For example, we’ve added oatmeal to make a gory kind of slurry, and Cream of Wheat to make a finer gore. Again, edible stuff. Again, avoid eating it.
You can add inedible things to the blood to add interesting textures, such as shredded cotton gauze or shredded cotton for strings. Don’t eat cotton.
For one shot in Flesh of my Flesh, we built skeletal structures using coat hangers, wrapped foil around the coat hangers, dipped huge coffee filters into fake blood, squeegeed the filters off, and wrapped them around the foil armatures. Not only did we get really great looking parts, but the reflectivity of the foil added a great effect of translucency.
I’ve seen that while real blood soaks in very convincingly to clothes, fake sugary blood does not perform so well, but this performance can be improved if the clothing is wetted down with a mister to speed absorption. (that’s a spray mister — not a male paramour)
As with all practical effects, set up a few tests before you shoot and try different variables (thinning out the blood with water to make it more spurty, for example). When you show up on set, have the best blood you can for the shoot, and be prepared to do a little on-the-fly modifications, too, just in case things change once you’re there.
‘Cause things will change on set, and people who already plan for that are people who are valuable to have on set.