Advanced Light Control Techniques Every Photographer Must Master

4. Using Colored Gels for Creative Control

• Correction — match dissimilar light sources (e.g., flash to tungsten or daylight). Common correction gels: CTO (Color Temperature Orange) and CTB (Color Temperature Blue).
• Creative — add color to backgrounds, rims, highlights, or whole scenes to set mood, direct the eye, or tell a story (neon, cinematic teal/orange, moody blues, etc.).

Keeping the distinction clear helps: use correction gels when you want neutral color reproduction, and creative gels when you want color as part of the image language.

Basic Terminology and Practical Notes

• CTO / CTB — used to shift color temperature.
  • CTO → warms toward tungsten (~3200K).
  • CTB → cools toward daylight (~5600K).
  • Also available in fractional strengths (¼, ½ CTO) for subtle shifts.
• Color correction for fluorescents — use magenta/green correction gels (or camera correction) to remove green cast.
• Saturation and transmission — gels are filters: they block some light. Strong, saturated gels reduce light output (often 0.5–2 stops depending on gel and layering).
• Heat and mounting — don’t attach paper-like gels to hot tungsten heads without a frame. Use gel frames, holders, or use LED heads (safer).
• Additive vs subtractive — light mixing is additive (RGB), but gels work subtractive (they filter). Stacking gels multiplies transmission curves and changes hue and brightness.

Workflow Choices (How to Make Gels Read Well on Camera)

Two typical strategies depending on what you want to control:

1. Neutralize one light, color the others
   1. Set camera WB to match the main light (e.g., 5600K for daylight key).
   1. Place creative gels on background/rim lights — they’ll show clearly against the neutral key.
2. White balance for mood, then gel for accent
   1. Set a warm WB (e.g., 3200K) to make the scene warm, then use a blue gel on a rim to create contrast.
   1. Shooting RAW lets you refine WB in post, so don’t be scared to experiment.

Metering tip: gels reduce light. If using TTL, the system compensates; with manual flash or continuous light, meter after gelling or increase power/ISO/longer exposure.

Concrete Example Setups (Step-by-Step Recipes)

These are starting points — tweak to taste.

1) Cinematic Teal-Orange Portrait (Classic)

• Goal: Subject warms (orange/skin), background cools (teal).
• Setup: Key = softbox slightly warmed with ¼–½ CTO; Background = Par or Fresnel with deep CTB or blue gel; Rim = small speedlight with a magenta or purple gel (optional).
• Camera starting point: ISO 100–200, shutter 1/125 (flash sync), aperture f/4.0. Key about 1 stop brighter than background.
• Why it works: Warm skin tones contrast strongly with blue/teal background — complementary feel that draws attention to the face.

 2) Complementary colors

• Goal: High-contrast, colorful, stylized night look.
• Setup: Left key = speedlight with deep magenta through a stripbox (narrow); Right rim = speedlight with cyan through a grid; Background = small LEDs set to saturated color or a gelled par.
• Tip: Flag lights to avoid spill on opposite side; raise contrast with a dark background.
• Why it works: Complementary and near-complementary colors (magenta and cyan) create pop and separation.

3) Product — Glossy Bottle Highlight

• Goal: Controlled bright highlight, deep shadows to emphasize shape.
• Setup: Use a snoot with a warm gel (amber/orange) to create a small highlight on the label; use black flags to cut unwanted reflections; add a subtle blue-gelled back light for rim separation.
• Why it works: Narrow, colored highlight draws eye to brand/logo and separates product from background.

4) Drama with Gobos + Colored Gels

• Goal: Patterned shadow (venetian blind) in a specific color.
• Setup: Place a gobo (slatted board) between a fresnel and subject. Put a saturated gel (e.g., deep teal) on fresnel so the pattern casts colored bands across the scene.
• Why it works: Patterned color adds narrative (e.g., “interrogation” or “late-night office”) and texture.

5) Background Gradients and Silhouettes

• Goal: Color gradient behind a silhouette.
• Setup: Use two lights aimed at a backdrop: one with a warm gel (left) and one with a cool gel (right). Gradients form where they overlap; subject in front becomes a silhouette.
• Why it works: Overlapping colors create pleasing blends and separation without touching the subject.

Mixing and Advanced Techniques

• Stacking gels — place two gels together to create a custom hue or deepen color; remember you’ll also darken output. Use stacking for fine control (e.g., blue + magenta → violet).
• Half/Graduated gels — cut a gel in half, clamp only top half to background light to create a subtle top-to-bottom gradient.
• Fractional CTO for skin — instead of full CTO, a 1/4 or 1/2 CTO warms skin gently without making highlights orange.
• Color + grid/snoot — combine gels with grids/snoots to place colored light exactly where you want without spill.
• Use reflectors to control colored fill — a white reflector will reduce contrast of a gelled key but keep the color; silver increases intensity.

Skin Tone and Color Sensitivity

• Human skin is judged quickly — strong colored light on faces can look stylized or unflattering. If you want a colored face, consider:
  • Keeping key mostly neutral and using gels for rim/background.
  • If coloring skin, soften the gel (fractional CTO) and reduce saturation.
  • Check results on a calibrated monitor (or neutral color card) to ensure tones remain pleasing.

Practical Troubleshooting

• Unwanted color contamination (spill): Flag the light, use grids, or move lights further away.
• Gels too dark / losing too much light: use a stronger light head, lower the shutter for continuous lights, or use TTL so the system compensates.
• Skin looks unnatural: reduce gel saturation or warm/cool the key only slightly; keep fills neutral.
• Hot heads melting gels: use heat-resistant gel frames or switch to LED/HMI heads.

When to Use Which Gel

• CTO (¼ → full) — warm skin, match flash to tungsten, create sunlit warmth.
• CTB — cool backgrounds, match daylight to tungsten lights, create moonlight feel.
• Magenta/Green — fluorescent corrections or stylized color (magenta pop).
• Deep Blue / Cyan / Teal — moody, cinematic, background/cool separation.
• Orange/Amber — sunrise/sunset feel, cozy warmth.
• Yellow/Red — theatrical warmth, retro/sepia feels.

Practice Exercises (Try These)

1. Two-Light Teal/Orange Portrait: Key = neutral softbox; rim/back = blue gel; small warm gel on hair. Shoot RAW, experiment with WB.
2. Neon Split Lighting: One side magenta, other side cyan — use narrow modifiers. Flag to prevent mixing on the face.
3. Product Spotlight: Snoot + white reflector to bounce a little colored light into shadows for subtle color accents.
4. Gradient Backdrop: Two different gels on two lights hitting a seamless; vary power to shift gradient center.
5. Gobo Storytelling: Gel a fresnel, cast a patterned shadow (blinds, leaves) across a subject — try different gel colors for mood change.

Final Tips

• Always shoot RAW. You’ll retain headroom to tweak hue/saturation and white balance later.
• Test and record recipes. Save gel, distance, power and camera settings as “recipes” you can reuse.
• Use a color card as a sanity check for skin tones when you’re combining heavy gels.
• Start small. Use fractional CTO/CTB or dilute a color by stacking a lighter gel first; ramp up saturation after you see the result.

Some Predefined Settings – for your concept

A. Film Noir / High-Contrast Portrait

Mood: Dark, mysterious, classic noir
Use Case: Dramatic headshots, moody editorial

Settings:

• ISO: 100
• Shutter: 1/160s
• Aperture: f/4
• Lens: 50mm f/1.8
• Flash: Single bare strobe or small softbox, 1/2 power, positioned 45° above subject, camera-left
• Modifier: Flag to block light from spilling on background
• Background: Black

Look: Deep shadows on one side of the face, strong rim definition if positioned slightly behind.

B. Cinematic Sunset Rim Light

Mood: Warm, ethereal, cinematic glow
Use Case: Outdoor storytelling, romance, travel portraits

Settings:

• ISO: 200
• Shutter: 1/200s
• Aperture: f/2.8
• Flash: Off-camera fill with 1/4 power, softbox, camera-right to lift shadows
• White Balance: 5600K
• Sun: Behind subject (rim light)

Look: Golden halo around hair/shoulders, subtle fill on face for balanced exposure.

C. Sci-Fi / Color Contrast Mood

Mood: Futuristic, edgy, stylized
Use Case: Concept art, music photography, fashion

Settings:

• ISO: 100
• Shutter: 1/160s
• Aperture: f/4
• Flash 1: Key with cyan gel, 1/2 power, 45° front-left
• Flash 2: Rim/backlight with magenta gel, 1/4 power, behind subject
• Background: Dark neutral

Look: Strong color separation, dramatic contours, almost cinematic poster feel.

D. Rainy / Wet Street Cinematic Mood

Mood: Moody, reflective, noir-like urban
Use Case: Street portraits, film stills

Settings:

• ISO: 400
• Shutter: 1/100s (slightly slower to capture ambient lights)
• Aperture: f/2.8
• Flash: Small softbox on-camera or off-camera at 1/2 power for face highlight
• Environment: Wet streets, neon/traffic lights reflecting
• Lens: 35mm f/1.4 for wider context

Look: Reflective puddles catch neon or streetlights, subject highlighted against dark urban background.

E. Moody Interior / Window Light + Flash

Mood: Cinematic drama, subtle storytelling
Use Case: Interiors, lifestyle, filmic portraits

Settings:

• ISO: 200
• Shutter: 1/125s
• Aperture: f/2.8
• Flash: Fill at 1/4 power with softbox opposite window light to balance shadows
• White Balance: 5200K (neutral daylight)
• Modifier: Window light as key, softbox as fill

Look: Natural light falloff, soft shadows, cinematic “slice of life” feel indoors.

F. Bright, Airy Portrait

Mood: Clean, cheerful, soft shadows
Use Case: Lifestyle, headshots, family portraits

Settings:

• ISO: 100
• Shutter: 1/200s (sync with flash)
• Aperture: f/2.8 (shallow depth for creamy background)
• Flash: Key light at 1/2 power, softbox, camera-left at 45°
• Fill: Reflector opposite key light to soften shadows

Tips: Position subject near a window, if possible, to add subtle natural rim light.

G. Dramatic Moody Portrait

Mood: Low-key, contrasty, cinematic
Use Case: Fine art, editorial

Settings:

• ISO: 100
• Shutter: 1/160s
• Aperture: f/4
• Flash: Single beauty dish, 1/1 power, 2–3 ft from subject, slightly above eye level
• Modifier: Flag one side to block light and create shadow gradient

Tips: Keep background dark (black cloth or wall) to enhance drama.

H. Product Photography – Crisp, White Background

Mood: Clean, commercial, high key
Use Case: E-commerce products

Settings:

• ISO: 100
• Shutter: 1/160s
• Aperture: f/11 (ensure sharpness across product)
• Flash: Two strobes at 1/2 power each, large softboxes, one on each side
• Background: White sweep lit by 1/4 power strobe to blow out

Tips: Use a tripod and remote trigger to eliminate camera shake.

I. Outdoor Golden Hour Portrait with Fill Flash

Mood: Warm, glowing, balanced shadows
Use Case: Engagement shoots, outdoor portraits

Settings:

• ISO: 200
• Shutter: 1/200s
• Aperture: f/2.8
• Flash: Key on-camera or off-camera at 1/4–1/2 power to fill shadows
• White Balance: 5600K (to balance warm sun)

Tips: Position sun behind subject for rim lighting, flash as subtle fill.

J. Creative Colored Gel Lighting

Mood: Moody, artistic, dramatic color contrast
Use Case: Music portraits, concept photography

Settings:

• ISO: 100
• Shutter: 1/160s
• Aperture: f/4
• Flash: Key light with blue gel at 1/2 power, camera-left; rim light with red gel at 1/4 power, behind subject
• Background: Dark or neutral

Tips: Experiment with complementary gels (orange/teal, purple/yellow) for strong visual impact.