LEE Filters in Theatre: Old Lanterns, New LEDs and the Set Itself

LEE Filters gel is still one of the most useful tools in a theatre, whether your rig is forty years old or brand new. It turns tired tungsten lanterns into a full colour palette, it fixes and extends white LED fixtures, and off the lighting bars it becomes a scenic material in its own right.

This guide is for lighting designers, production managers, school and community theatres, and venue technicians. It covers three things: getting more from older fixtures, using LEE's LED specific Zircon range on modern white LED fixtures, and why gelled white light is often a better choice than RGB colour mixing. Then we go off the bars and into the workshop, with creative ways to use gel in set building, props and effects.

Giving older fixtures a second life

A venue full of tungsten profiles, fresnels, PAR cans and cyc floods is not a problem to be replaced. With a well chosen set of LEE colours, that inventory becomes a flexible, designer friendly rig for the cost of a few sheets of gel.

Why gel still makes sense on conventional fixtures:

• Every lantern can be any colour. A frame of gel turns a single white profile into a moonlight special, a sunset side light or a dramatic backlight, and you can change it between shows in minutes.
• Tungsten loves gel. A halogen lamp has a smooth, continuous spectrum, so filtered colours look rich and true. Many classic theatre colours were developed on exactly these sources.
• It protects your investment. Older fixtures often have excellent optics. Gel lets you keep using them while you phase in LED at your own pace.
• It matches old and new. When a rig mixes tungsten and LED, correction filters bridge the gap. 204 Full C.T. Orange warms a daylight LED down to tungsten, while 201 Full C.T. Blue and 202 Half C.T. Blue push tungsten cooler.

Colours that earn their place in a theatre gel drawer:

Heat is the enemy on tungsten. Deep, saturated colours absorb more energy and fade faster in a hot lantern. Fitting 269 Heat Shield between the lamp and the gel helps extend filter life, particularly in high wattage profiles and cyc lights.

Zircon: LEE's filter range built for LED

Many theatres have replaced tungsten with white LED profiles, fresnels and retrofit engines. Gel still works on these fixtures, but LED brings two problems: the concentrated output can fade standard filters faster, and a cool white LED can make a familiar gel colour look quite different from how it looks on tungsten.

LEE's answer is the Zircon range, developed specifically for LED sources.

• Much longer life. LEE states Zircon is engineered to be up to 200 times more durable than standard filter, holding over 85% efficiency for up to 20 months of continuous use. That figure comes from LEE's own testing at 11 hours a day, with the filter 1 to 2cm from the LED.
• Thicker and easier to handle. Zircon is made on a 180 micron base, more than double the thickness of a standard lighting filter, so it sits flat in a colour frame or a channel without curling.
• Designed for LED tuning. The range focuses on correcting and shaping white LED rather than heavy colour effects.

If you want the whole range on hand, the Zircon Warm LED, Zircon Cool LED and Zircon Correction lighting packs are a cost effective way to start.

Important: LEE's Zircon literature notes that Zircon is designed for LED fixtures only and is not flame retardant. Keep it off tungsten lanterns, and check the technical data sheet and your venue's requirements before using any filter outside a fixture.

White LED plus gel, or RGB colour mixing?

RGB fixtures are brilliant when you need colour to change live during a cue. But for many theatre jobs, a quality white LED with a LEE filter gives better looking light, more consistently, for less money.

• Better colour on people and costumes. A good white LED has a broad spectrum, and a gel filters that spectrum rather than building colour from a few narrow emitters. Basic RGB fixtures can struggle with skin tones, pastels and ambers, and can make some costume fabrics shift colour. Fixtures with extra emitters, such as RGBW or RGBA, improve this, but usually at a higher price.
• Clean, single shadows. In some multi emitter fixtures the colours do not fully blend before they leave the lens, so a performer can cast fringed or multicoloured shadows. A gelled white source casts one shadow in one colour.
• The same colour every time. LEE 162 is LEE 162 in any theatre, on any tour and in any year. RGB mixes can vary between fixture models, firmware and even production batches, which makes remounts, touring and matching new stock harder.
• A shared language. Lighting designers still spec looks by gel number. A plot that says "201 in the backlight" can be rebuilt by any crew, anywhere, without a show file.
• Lower cost per fixture. White LED fixtures generally cost less than full colour mixing models, and a sheet of gel costs a fraction of the difference. For a school or community venue, that can mean more fixtures in the rig.
• Simple to run. A gelled fixture needs one dimmer channel, not several colour parameters. Volunteers and students can rig, focus and colour without programming knowledge.

The honest trade off: a gelled fixture gives you one colour per show unless someone climbs up and changes it, and saturated gels reduce output. The strongest theatre rigs often combine both: RGB for cyc washes and colour changing effects, and gelled white LED or tungsten for key light, specials and anything that lights a face.

Off the bars: creative uses in set building and effects

Gel is a coloured, translucent, cuttable sheet that comes in hundreds of colours. Set builders, prop makers and designers can use that as a material, not just a lighting accessory.

1. Stained glass windows. Cut shapes from several colours, sandwich them between sheets of clear acrylic, and lead the design with black tape or strips of 280 Black Foil. Backlight it with a single white source and the window glows in full colour. Change the backlight intensity and the "time of day" changes too.
2. Glowing props and lightboxes. Line a lantern, potion bottle, treasure chest or sci fi control panel with gel over a small battery LED. A strip of Zircon diffusion such as 810 hides the individual chips so the glow looks even.
3. Shadow screens and shadow puppetry. A frame of 216 White Diffusion or 129 Heavy Frost makes a light, cheap shadow screen. Put two sources in different colours behind the performer and each casts its own coloured shadow, a striking effect for dance and children's theatre.
4. Rear projection surfaces. Diffusion stretched on a frame can also take a rear projected image, useful for small scenic projections, windows and screens within the set.
5. Frosted and icy scenery. 253 Hampshire Frost and 410 Opal Frost applied to clear panels read as frosted glass, ice walls or shower screens, and they hide backstage clutter while still letting light through.
6. Fire without flame. Combine 019 Fire, 164 Flame Red and 105 Orange in a low fixture behind a fireplace or campfire unit, add moving silk or a flicker chase, and you have safe, convincing firelight.
7. Water and caustics. Crumpled 273 Soft Silver Reflector bounced from a moving source throws rippling water light across a set or cyc. Our creative ways to use LEE Filters guide covers this and other techniques in more detail.
8. Period practicals. Wrap the inside of a practical lamp shade with 103 Straw or 162 Bastard Amber so a modern LED globe reads as an old oil lamp or gas light.
9. Masking and spill control. 280 Black Foil can be shaped by hand to trim spill off scenery, block light leaking through gaps in flats, and make quick cutters in the workshop.
10. Front of house and opening nights. Zircon is also used for architectural lighting, so the same filters can colour foyer, facade or bar lighting to match the show's palette.
11. Design and teaching. A LEE swatch book held in front of a torch lets a designer, director or student test a colour idea in seconds, before a single sheet is cut.

Practical tips for theatre crews

• Label every frame. Write the LEE number on the colour frame or the gel edge. It saves time at changeover and when you reorder.
• Cut with a template. Keep a cutting template for each fixture type so every piece fits first time and nothing touches the lens or lamp.
• Test under the real fixture. A colour looks different on tungsten, cool white LED and warm white LED. Check it in the actual lantern before committing a whole rig.
• Replace faded gel. Saturated colours fade over a long season, especially on hot tungsten. Swap them early so the look stays consistent from opening to closing night.
• Use the right range for the source. Standard LEE filters for tungsten and general use, Zircon for LED only.
• Check fire requirements for scenic use. Before gel becomes part of the set, check the product's technical data sheet and your venue's fire safety requirements, and keep filters well clear of hot lamps and practicals.
• Store it flat and dry. Rolls stay upright in their boxes, and sheets stay flat in folders away from sunlight.

Frequently asked questions

Can I use standard LEE gel on LED theatre fixtures?

Yes. Standard filters work on LED, but they may fade faster under intense LED output, and colours can look different on a cool white source. For correction, diffusion and density on LED, Zircon is designed to last much longer.

Can I put Zircon on a tungsten lantern?

No. Zircon is designed for LED fixtures only. Use standard LEE filters, with 269 Heat Shield where needed, on tungsten.

Is gelled white LED really better than RGB?

For key light, faces, costumes and specials, gelled white light often looks more natural and is more consistent between fixtures and venues. RGB wins when you need colour to change during a cue. Most rigs benefit from both.

Does gel reduce brightness?

Yes. Every filter passes a percentage of the light, and deeper colours pass less. Each LEE filter's technical data shows its transmission, so you can plan for it.

What should a school or community theatre buy first?

A small kit covers most shows: 162 Bastard Amber and 103 Straw for warm cover, 201 Full C.T. Blue for moonlight, 119 Dark Blue for backlight, a red, green and blue for the cyc, 410 Opal Frost for softening, and a fire gel such as 019. Add Zircon Warm Amber and Minus Green if your rig includes white LED.

Can gel be used as part of the set?

Yes, for windows, glowing props, frosted panels and shadow screens. Check the technical data sheet and your venue's fire safety requirements first, and keep filters clear of hot lamps.

Where to buy

Black Flag Distribution is an authorised Australian distributor for LEE Filters, and our LEE Filters lighting gels guide walks through the full range.

We support our valued specialist retail partners and prefer that you purchase through them wherever possible: use the store finder to locate your nearest authorised dealer. If you would rather buy direct, we can also facilitate your order.

Planning a season, fitting out a school theatre or matching tungsten and LED in the one rig? Talk to us at sales@blkflag.com.au.

Sources

• LEE Filters: Zircon range
• LEE Filters Direct: Zircon LED gel filters
• LEE Filters: Lighting filter packs