The awkward, technical truth behind Hollywood sex scenes

Actors are human, too. Many have described feelings of insecurity about their body or appearance prior to filming sex scenes, including Allison Janney, who did her first-ever sex scene for Showtime's "Masters of Sex."

When interviewed by The New York Times about the experience, she said, "I'm one of those actors who fall into the camp of never wanting to look at themselves on camera ever. I do not and will not because I am my worst critic. I think it was the hardest thing I ever had to do, to pretend that I was having an orgasm on screen."

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Film and television shooting schedules are often arranged out of order. This can be based on when certain actors are available or what locations the production team has access to on a given day.

This means that actors can potentially be scheduled to do a love scene even when they haven't yet met or bonded with their scene partner.

In an interview with New York magazine, Jenna Fischer said her wedding-night sex scene with John C. Reilly in "Walk Hard" was originally scheduled early on in the production schedule.

"That scene was actually on the schedule for my third day of shooting, and I went to the director [Jake Kasdan] and said, 'I think I need to know him a little more before we go at it,'" she told the publication.

As an audience member, it can be hard to watch a wildly passionate sex scene and imagine that the actors on screen aren't truly feeling the rush themselves. Actors, however, are professionals who are doing a job, and the actual act of simulating sex can be so choreographed, uncomfortable, and impersonal that it doesn't lend itself to an honestly sexy experience.

For starters, performing on a set is anything but private. Even "closed sets" have half a dozen or more crew members watching. And there are often specific directions actors have to take, so their focus is usually geared toward following the blocking and giving their best performance rather than feeling the heat of the moment.

That said, Vallée acknowledged that everyone is human, so occasionally there can be some real, physical feelings.

He said, "I've never seen an actor with an erection, in all of the films and the sex scenes that I've done, but it doesn't mean that I haven't seen a guy being excited. It's so technical, but we're humans, and they're naked, and they touch each other."

Even though sex scenes can be brief on-screen, they can actually take hours to film, whether it's due to makeup touch-ups, director's notes, or lighting changes.

While filming "Love and Other Drugs," Anne Hathaway told Entertainment Weekly that filming the sex scenes took a while since she had to have her body makeup touched up fairly frequently.

" ... I found that every time I put my robe back on, it rubbed all the body makeup off, and that added 20 minutes to filming," she told the publication.

Justin Timberlake also said that filming sex scenes for the movie "Friends With Benefits" was incredibly time-consuming. "It's actually kind of annoying, you're there for 12 hours, it's exhausting," he told the BBC.

When working with Dakota Johnson on "50 Shades of Grey," actor Jamie Dornan said he utilized humor to help everyone feel more comfortable during the sex scenes.

He talked about his antics on "The Graham Norton Show," saying, "My temptation is always just to try to make Dakota laugh, so sometimes I'll do things like, when there's a moment where I'm meant to, you know, orgasm, I'll be like, [makes the sports game organ 'Charge!' sound]."

Many producers and directors understand that watching a sex scene can be awkward for audiences.

Some directors, like Adrian Lyne ("Fatal Attraction"), want to keep the possibility of humor in sex scenes open, in hopes of making them more natural and approachable to audiences.

As Lyne told The New York Times, "You try and create a situation where there are possibilities. I've always thought that sort of grabbed sex is more fun than that statuesque sort of bedroom stuff."

He said that in "Fatal Attraction," the sex scene filmed over the sink wasn't meant to be taken too seriously.

"I knew [the scene] had humorous possibilities because there [were] plates and cups in the sink. If you don't get some humor in, the audience will laugh at you, because they're nervous watching it," he told the publication.

Productions often operate on what's known as a "closed set" during the filming of sex scenes.

Most film and television sets have hundreds of crew members working while shooting a scene. During closed-set shoots, however, the director and actors operate with a "skeleton crew" — the absolute minimum number of people required to shoot the scene.

As outlined in the SAG-AFTRA nudity rider, actors can request a closed set prior to shooting and may add any other special conditions that they and a producer agree upon.

This can include anything from ensuring the room is a certain temperature to requesting that non-essential crew people turn their backs during shooting.

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As outlined by SAG-AFTRA, actors decide how much nudity and simulated sex they are willing to do. If production wants to cast an actor who refuses to do nudity for any reason, they often use body doubles.

And just like leading actors, body doubles have nudity riders in their contracts that explicitly outline the details of their nudity agreement with production.

Multiple body doubles can even be used to portray one character. Isla Fisher told Entertainment Weekly multiple doubles were used for her character's nudity and sex scenes in the film "Wedding Crashers."

She said, "I had a hand double for the under-the-table scene. I had a breast double for the boob-in-the-face, and I had a butt double."

Things can get a bit more complicated if a scene requires the actor's face and nude body to be seen at the same time. In these instances, post-production CGI is used to splice together the actor's face and their double's nude body.

This technique was used in the season-five finale of HBO's "Game of Thrones," when Lena Headey's character, Cersei, takes her nude walk of atonement. Her stand-in, Rebecca Van Cleave, served as Headey's nude body double for the scene, according to Entertainment Weekly.

Have you ever watched characters in the throes of passion and wondered just how naked the actors really are?

The truth is, when a body part is out of frame or not visible due to how the bodies are positioned, actors are most likely wearing a modesty patch.

"It's like a big Band-Aid that goes from the front, covering their crotch, and then tucks in the back. It does not look very comfortable!" Michelle Ashford, creator of Showtime's "Masters of Sex" told Glamour magazine.

As for covering penises? "They wear a sock. Literally. A tube sock over their penis," Ashford told the magazine.

Nude-colored underwear, full-body makeup, and other coverings are also used to shield certain body parts from the camera.

When simulating sex, props like pillows are placed between actors and prosthetics can be used to create the illusion of sex.

For other directors, such as Jean-Marc Vallée ("Dallas Buyers Club," "Wild," "Big Little Lies") choreography can muddle up the natural rhythm of a sex scene.

As the director told the The New York Times, he prefers not to choreograph and block sex scenes ahead of . time.

When asked by The New York Times about his preference between choreography and blocking during sex scenes, he said,

"There [is] no specific choreography, but there's a way of setting a tone. Restricted crew, it's just available light where we can move 360 degrees with the camera — this is the intention, and let's see where it goes from there," he explained to the publication.

"[In "Wild"] it wasn't specifically planned for this guy to take Reese [Witherspoon], to turn her on her back, and take her from behind, but it just happened as we were shooting. And [in "Dallas Buyers Club"] with Matthew [McConaughey], at one point he had a threesome, with two girls in this trailer home with his friend watching him, and he was on fire," Vallée explained.

Whether or not an actor is willing to allow improv during the filming of sex scenes is something that can be negotiated in their SAG-AFTRA nudity rider.

For any scene, blocking is a typical first step. Directors do a walk-through with actors, discussing when and where they should move during the scene.

The same is often done during sex scenes. Some directors, like David Fincher ("Gone Girl," "Fight Club," "Seven"), will outline specific movements prior to filming.

For example, Neil Patrick Harris told Out magazine that the sex scene in the film "Gone Girl" was choreographed in a detailed way.

"We had to rehearse the sex scene with David, like every inch of it — 'Then you put your mouth on his d--- here, and then this number of thrusts, and then you ejaculate,'" he told the publication. "It was weird because we're technically breaking down the sex scene. He wanted it to be almost robotic, that we know exactly where we are, position-wise, where everything goes."

If you're seeing a naked actor on screen, it's important to know that legal contracts that outlined the details of the nudity were signed prior to the actor accepting the role.

SAG-AFTRA, the entertainment industry labor union, designates a nudity rider as a requirement in contracts for roles that require "nudity, partial nudity or simulated sex acts."

This document is negotiated by the actor, their representatives, and the production team, and within the rider are detailed descriptions of what the actor is willing to do on screen.

This includes scene information, the type of nudity required, limitations on usage of the footage, and any details or terms the actor and producer agree upon.

It's not unusual for a nudity rider to include minute details such as exactly which body parts are visible, how much of the body part can be seen, and for how long the body part is shown.

Although the nudity rider is a contract, SAG-AFTRA reiterates the importance of consent, saying, "Remember, even if you have signed a nudity rider, you have the right to withdraw consent at any time prior to [the] filming of the scene."

If an actor is working on a non-union film, they are not protected by the union. This is why many actors choose not to do nudity or simulated sex in any non-union productions.