Managing for church projection
Jan 1, 1999 12:00 PM, Peter H. Putman
Churches, by nature, are environmentally hostile to projection. Traditional CRT projection systems are no match for ambient light from outside and warm light from sconces, scoop lights, down lights and stage lighting. It has taken the evolution of lightvalve projectors (LCDs, DLP and ILA) to generate sufficiently bright video images. Instead of 150 to 250 ANSI lumens, we now have 20x more light in a single projector. That extra light energy may expand the upper end of image grayscales, yielding brilliant whites and bright colors, but the low end is still limited by ambient light that hits the screen surface.
Lighting with purpose There are two lighting vs. projection conflicts. The first occurs when large areas of a pulpit must be illuminated for better viewing of a minister. The second occurs when preset internal lighting effects are used to create a dramatic mood for different services or different sections of a service.
In both cases, light can spill onto a screen surface if not carefully focused, which can fog the image, lower contrast and make it harder for people in distant rows to see any image magnification (IMAG) video or keyed titles and hymn lyrics. Ambient light from windows aggravates both problems.
When installing a large-screen display system, the most practical way to avoid these problems is to cycle through all existing lighting cues to see which backdrops or walls can remain unlit. Checking lighting cues and setting all house lights to full on may reveal a better screen location.
You may discover that there are no ideal locations for a screen; in fact, existing stage wash and spotlighting may illuminate every wall surface. In this case, modifications will have to be made to use tighter spots, washes with barn doors, extended snoots on down lights and occasional lighting flags.
If modifying lighting to accommodate a screen creates an asymmetrical light pattern, a banner or similar backdrop lit with a glow light can balance out the screen. A second projection screen may even be in order. Also, try accent lighting to either side of the screen.
The eye is drawn to the brightest object in a scene, so lighting cues during video segments should be preset to draw the eye to the minister or the projection screen. Banners and floral decorations can glow during an IMAG or pre-recorded video segment; do not bring them up too high.
If the screen surface is offset from a background, provide a mid grayscale color for that background and softly light it to a dark gray. This works well with projected images. Viewers will experience less eyestrain and faster adjustment to full house lighting.
Lighting for depth Although our eyes are forgiving, the same can't be said for video cameras. You must light the pulpit and any proscenium or stage areas to provide a reasonable grayscale, avoiding any high-contrast lighting between subjects and backgrounds.
Three-point lighting on any person not standing against a wall is a must. Ministers are generally downstage and should be lit to set them off from any decorative backdrops. In addition, the areas behind them should not fade into blackness.
If we light a heavy drape behind a minister at a lectern, we may see only a slight difference in light intensity from foreground to background. A video camera, however, will expand that contrast and see several f/stops of light levels between the minister's face and the drapery. It may drop to almost black.
As a rule of thumb, light any fixed areas with a key lamp, a fill at one f/stop lower and a hair light at one f/stop higher. Provide a background about two f/stops below the key light to prevent eye fatigue. This lighting with moving subjects is difficult, so a stage wash with PAR-type lighting cans will be called for. Back light the subject from additional flood lamps and barn doors about one f/stop higher.
You will need a high angle for any back lights to prevent shining lights directly into the audience's eyes. If impossible, then extra barn doors will be required. These will provide depth between foreground and background objects on IMAG images. Keep any wash lighting on sets, flats or banners at two f/stops below the front wash lights.
Also, use light straw gels on focused lamps to reduce glare. Cameras will read all light ambers and straws as white once they are balanced to tungsten lighting. Straw or cool blue gels additionally work for back lights and set/flat lighting. Light blue gels reduce contrast and color saturation, providing more definition and depth between the subject and backgrounds.
You may run into tricky situations mixing ambient light and stage lighting, particularly if your church has a lot of high windows. In this case, use cooler (bluish) gels on many of your lights for correct white balance. If you are ambitious, apply correction gels directly to certain windows to change the color temperature of outside light.
Effective lighting for church projection is not all that complicated, but it does take practice to set lights and balance levels for the human eye and video cameras. Experiment with room and stage lighting to see which combinations of settings and instruments give the best-looking projected images while providing a warm, intimate feeling.
Do not depend on the low-light settings on your cameras. They introduce noise and grain that looks worse when projected. Focused lights create more contrast, and high contrast increases apparent sharpness in projected images. Contrast also punches up colors and createsdepth and space-all keys to getting the best image from the projection system.
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