Tattoos often need to be covered up, and depending on the need of clients, any shop with this kind of service could do some helpful stuff. Cosmetics can cover most anything on the skin and there are all sorts of products that are thick enough to provide a covering that works. These could be items found in use for theater and the film industry.
The need for this kind of service will be temporary, perhaps when someone needs to go on air and does not want tattoos to mar the shoot. The tattoo cover up makeup could be done by beauty experts or makeup artists. In film shoots, when actors or actresses have many tattoos, there will often be need to cover them up for shooting.
The film, the director and the story might find these too inconvenient. Or most probably the roles being played says that there should not be any kind of skin decoration that should be seen on the actors. There is always a way of providing covers like these become effective, and the thickest of grease makeup could do the trick.
Theater personalities could have any kind of tattoo done, because these are signages of freedom or liberation. However, when the play demands that there be none of these found on stage, the actors need people to cover their tats up. The makeup personnel will do the work, and perhaps keep on retouching it if the cosmetics run.
As is usually the case when the filming or the stage play could become heated. Pressure to perform and demanding ways that might be found for any role could make actors sweat. Sweat is one of the primary enemies of makeup and sweating copiously could ruin the cover, thus there is a specialized type of cosmetic in use.
This is not something that may be used normally, because laying it on could really be hideous for normal use. But for the most colorful or blackest of inked designs on skin, they need to really thick. And sweat factors means that these products should have pancake qualities that are actually firmer than pancake items.
Experts for these have studied how covering up could work, so that actors are better able to move or not be impeded by the stuff done. Prosthetics and synthetic covers could work, but these would be more expensive when the coverage is only for a small area of the body. The area could be well exposed during the movie, like the arms, hands, neck or face.
The actors of course have all the freedom to wear their tats anywhere in public. But in films, directors control how they look. But the tattoos have not been a problem for the industry, but in years before the preference was for players that had no bodily markings that could mar the shooting of movies, but today this no longer applies.
Tech of course has much to do with this development and sporting tattoos have really become an in thing with famous movie and theater personalities. The film studios no longer worry about their artists having marks on their skin. The specialists in production could do anything to take out anything that should not be on celluloid records.