One might think that a fabric company has little to do with lighting. After all, while scenery and lighting design are inexorably linked, how important can fabric be to either? Yet the choices a designer makes in fabric, as with all the other elements, will directly affect the final look of the production. This series of articles discusses common types of fabric, why they are used, and challenges they may present to a lighting designer.

ANGLE, ANGLE, ANGLE

Lighting vis-à-vis fabric is nowhere more critical than when dealing with a sharkstooth scrim. Lit correctly, a sharkstooth scrim provides one of the most magical effects: the bleed-through. If the scrim is lit correctly, it can appear completely opaque; as the lighting is changed, the scrim will “dissolve,” allowing the scene behind it to “bleed through” the scrim or the scenery painted on the scrim. Continue the change, and the scrim will disappear completely, as if by magic. But what is the “correct” way to make this happen?

In real estate, the three most important factors are “location, location, location.” To create this effect with sharks-tooth scrim, the most important things to remember are angle, angle, angle. Combined with a stringent control of the lighting, the correct angle will make the task easy. Knowing the correct angle is simple: just think oblique or, if you prefer, steep, and you're well on your way.

We often get calls from less experienced users telling us that our sharkstooth scrim “doesn't work.” When pressed, the caller usually says that the scrim will not provide an opaque surface and that the scene behind the scrim is visible when the scrim is lit. Invariably, we find that one of two things is going wrong. First, prior to the bleed-through, the space behind the scrim must be completely dark. The key word here is “completely.” Any light behind the scrim reflects on the scene that the scrim is trying to hide, allowing the audience to see it, albeit dimly. Already, the magic is beginning to weaken. For a scrim to be most effective, the area behind it must be totally unlit; ideally, even running and exit lights should be masked from casting illumination. Of course, the brighter the lighting on the scrim itself, the less likely it is that anyone will see a glimmer or gleam shining from behind the scrim, but every effort should be made to keep the area behind the scrim completely dark until the “reveal” cue is running.

Now the area is as dark as possible (our caller assures us), but it still “doesn't work.” The scene is still visible through the lit scrim. Here's where the angle of the lighting is critical. Ideally, the lighting on the scrim is at such a steep angle that it cannot possibly illuminate the scene behind — so steep that any spill “buries” within a foot or so of the scrim. You must create a “trough” of space between the scrim and nearby scenery so that any light that spills through the scrim hits nothing and won't show to the audience.

The most common way to achieve this is to have some type of strip lighting at the top and directly in front of the scrim. The majority of the light from the strips washes the front of the scrim (with some spill downstage), and any excess light shines through into the empty space between the scrim and the scenery and is not visible. If you have extra line sets and a spare blackout drape, you can ensure this by hanging the drape about a foot behind your scrim at the upstage edge of your “trough” and flying it out moments before the bleed-through. You still need to control the spill upstage or the blackout drop will be visible, most particularly as it flies just before the bleed-through begins.

LOCATION, LOCATION, LOCATION

While the most common placement of lighting instruments for a scrim is above and directly in front of the scrim, that isn't the only position that will be effective. Remember: angle angle, angle! As long as your lighting is oblique and can wash the scrim, it doesn't have to be from above. If your scrim is in an extreme downstage position, for example, it can be lit with footlights; many think of these as anachronisms, but they're very effective for scrim washes. (In this case, the “spill” light is lost up in the flies, behind the proscenium and/or masking borders.)

In a “wing and drop” set, the strips can be mounted vertically on each side of the scrim; the spill, in this case, will wash off-stage between the wings downstage and upstage of the scrim. In all of these cases, a blackout drop is helpful but not necessary.

Having said that, it should follow what lighting positions will not work for a scrim. Sharkstooth scrim is, essentially, a series of holes tied together that will let lighting through. Lighting from the front of house will certainly light the scrim. Unfortunately, it will also light everything behind it. Moving to the box booms will only help if they create an angle so severe that the spill disappears offstage. Balcony rail is probably the worst position. Since “the angle of incidence equals the angle of return,” the rail will provide the maximum visibility of the scrim and the scenery behind it.

Equally important in making the scrim work its magic is properly lighting the scene behind it. If you want the scrim to disappear when the dissolve is complete, the lighting for the scene to be revealed must come from behind the scrim. Any lighting from in front may well reveal the upstage scene but will also continue to illuminate the scrim itself, and any scenery that may be painted on it. While this may be the effect you want to achieve, if you want the scrim to disappear, it cannot be lit. Your scene lighting should come from an electric upstage (and blackout drop) or from side positions upstage of the scrim.

All in all, lighting a scrim is fairly basic but very easy to get very wrong. When done correctly, it can be a magical effect; when the lighting isn't controlled, it can be a painful mess. Sharkstooth scrim presents the most common challenge to lighting designers. In our next article, we'll discuss other fabrics common to production and the challenges they may present to lighting.

Peter Monahan has an MFA in lighting design and is a sales representative for Rose Brand. He can be reached at pmonahan@rosebrand.com.

Scrim FAQs

Does it matter in which direction the “tooth,” or opening in the scrim, is oriented? The tooth is about twice as high as it is wide, and this is the common orientation when sewing the scrim. The properties, however, are not affected if the tooth is rotated. Another common reason for rotating a scrim is to combat the moiré effect: this is caused when holes of the same size are lined up with one another, causing a wavy, blurring look to whatever is seen through. As this can cause discomfort to audiences, it should be avoided; rotating one of the scrims will ensure that the “teeth” do not line up. Trying to maintain at least 6' between scrims will also minimize this effect.

What side of the scrim should face the audience? When you feel a sharkstooth scrim, one side is fairly smooth, while the other has more texture, where the threads pass over one another. While it does not appreciably affect the use of the scrim, more texture gives the light more surface area to hit and is slightly more visible to the audience. We generally place the textured side towards the audience.

Can you project onto sharkstooth scrim? Short answer: yes, but you may not want to do so. Since scrim is a series of holes tied together, it wants to be lit at an extreme angle. If you are projecting images onto it, you will probably want to use a fairly direct, flat angle, which means much of the image will continue through the scrim and strike whatever is behind. The image on the scrim itself will be degraded, both by the secondary reflection from behind the scrim and by the low quality of the surface. The image will be recognizable but not of high quality. That said, projecting patterns or abstractions onto a scrim is often very effective, especially as the secondary reflection may provide additional depth and dimension.