There's been some questions concerning the use of 'rubber/latex' for film work- to which I think it's about time I ponied up a little help & hopefully some enlightenment to your options when it comes to creating our ghoulish friends.
Lets start with a few basics...
1] Just what is latex?
In a nutshell- the quick response is "Do you know what a rubber tree plant is? Latex rubber comes out of that."
Now- in this day and age of materials that's not necessarily true anymore- there are man-made "latexes" but then, the true definition of latex precludes man-made materials... So here's the official make-up vernacular:
"All natural rubber originates in the Hevea tree, and it starts its journey when the tree is tapped."
Here's a link for REALLY in-depth research into natural latex/rubber:
History of Latex
2] There's more than one type though...
There's actually quite a few varying types of latex materials- some that are quite safe to "paint onto" the body as a type of clothing! Here's one example:
Deviant Arts- please note, some of the photos presented are a bit "racey"
Deviant Arts as a website is not for the faint of heart, or more aptly for the prudish- I offer this site link as a product reference- what they offer is quite spectacular, but it's use is sometimes rather... "Sensual" if not outright decadent/erotic...
This is a high-end product, extremely expensive and really not of much use for horror make-up let alone low/no budget horror films...
Now: Let's go over a few of the types best usable for our needs...
3] Molde or "Slush Use" latex
These are latexes most often used for masks,
limited body application and for prosthetic construction- put "mold making latex", "liquid latex" or "pottery latex" into your search engine [or Google...] and you'll come up with a huge number of retailers.
These latexes almost always have an ammonia base [creating a "litter box" smell to stink out the high heavens!] that have to "dry" before use- I use quotes in this case because latexes as a whole do not "dry" as they "cure"- proteins in the latex [natural latex, please remember] begin to bond as the ammonia off-gasses and thusly create the pliable molecular material you eventually wind up with!
4] "Cosmetic" Latex
There are cosmetic versions of this that can be used [limited- always limited!] on the face, but you can still smell the ammonia in them quite readily! These really aren't much different than the slush types except that it is a finer grade- most useful for applications where incredibly close scrutiny would be possible.
This is the type you'll
always find on your store shelves during Halloween shopping- it is the least volatile, least "stinky" and ["sadly" for the pro] the cheapest grade for the type of application latex you'll find.
Honestly? If you're a pro or a purist, you'll want to get a high cosmetic grade from a shop [larger cities often have specialty cosmetic stores] or reputable on-line vendor for this type of grade.
But if you're "in the real [reel?] world- the "cheap stuff" will do just fine! The idea here is to have fun, right?
5] Foam Latex
This is actually a HUGE category of latexes- suffice it to say, there are "self curing" 1-part, 2 part, 3 part and 4 part types- then there are "oven cured" 1, 2, 3, 4, parts and then varying degrees there-in! This particular category should get its own forum quite frankly- suffice it to say that unless you're making a massive amount of built-up prosthetic facial appliances, your own body parts or such things, this type of latex is highly complex & outside the scope of this precursory Opening Discussion!
6] Allergies? People are allergic to this stuff?!
Sure are and sure can! The very first link I've given you is a database specifically for those who may have latex allergies so bad they can't even have rugs that have latex backings!
The easiest way to test for latex allergies is often the most overlooked... If it's not going on your body...
ASK!
Those with allergic reactions to latex will quickly let you know! If they don't happen to know though, there's a less invasive way to find out without dipping them in a vat...
Extend the right or left wrist of your actor and a apply a thin, quarter to 1/2 dollar [do we even have those anymore?] sized blob of your latex on that spot- dry with a hair dryer and let set for 30 minutes.
After 30 minutes, unless the actor has already scratched it off with a certain vigor or madness, peal off the spot and see if the skin has puckered, swelled or blistered- if it has, no latex need be used- go for cosmetics & that person is relegated to the background.
This is just a precursory Opening Discussion [OD?] so I know there's all manner of things that have gone unmentioned.
Ask, and ye shall receive.
When it comes to make-up and FX [FX= Special Effects in film/TV parlance] "the dumb question is the one not asked" could literally mean life or death in some instances!
Please- ASK.
If you have information to offer up- DO SO!
Methods, products, materials and techniques change every year- I'm not the end-all authority on such subjects; we all learn when we all contribute, right?
Let the learning begin!
Cleric