I. Understanding the Basics:
* Inverse Square Law: This is *crucial*. Light intensity decreases exponentially as distance increases. A subject twice as far from the flash receives only 1/4th the light. This principle dictates how you position your flash to control shadows and highlights.
* Diffusion and Size of Light Source: A small, bare flash creates harsh shadows. The larger and softer the light source, the softer the shadows. Modifiers like umbrellas or softboxes increase the light source's apparent size, softening the light.
* Color Temperature: Flash has a cooler color temperature (around 5500-6000K) than many indoor ambient lights. Correcting this with gels can prevent color casts.
* Ambient Light: Don't ignore the existing light! Use it to your advantage, balancing it with your flash for a more natural look.
II. Gear You'll Need:
* Speedlight (Flash): Any speedlight with manual power control will work. TTL (Through-The-Lens) metering is helpful but not strictly necessary.
* Flash Trigger (Optional but Recommended): A flash trigger allows you to use the flash off-camera, dramatically increasing your creative options. Triggers usually consist of a transmitter on your camera and a receiver attached to the flash.
* Light Stand (Optional but Recommended): To hold your off-camera flash.
* Light Modifier (Essential): This is where you shape the light. Choose from:
* Umbrella (Shoot-Through or Reflective): Inexpensive and easy to use. Shoot-through umbrellas provide softer, more diffused light. Reflective umbrellas are brighter and can be focused.
* Softbox: Creates even softer light than an umbrella. Rectangular softboxes produce a more natural, window-like light.
* Beauty Dish: Produces a punchy, directional light with a soft edge. Great for portraits.
* Reflector: A reflector bounces ambient light or flash back onto the subject, filling in shadows. Silver reflectors are brighter and more contrasty; white reflectors provide softer fill.
* DIY Diffuser: Even a piece of white fabric or parchment paper can work in a pinch to diffuse the flash.
* Gels (Optional): To adjust the color temperature of your flash.
* Reflector Holder/Stand (Optional): Makes using reflectors much easier.
III. Shooting Techniques:
* On-Camera Flash (Least Recommended, but Possible):
* Direct Flash: Harsh and unflattering. Avoid unless you're going for a very specific, stylized look.
* Bouncing Flash: Angle the flash head upwards to bounce the light off a ceiling or wall. This creates softer, more natural-looking light. Ensure the ceiling/wall is white or a neutral color to avoid color casts. Pay attention to the direction the light is bouncing. Bouncing off a wall behind you will cast unflattering shadows.
* Diffusing On-Camera Flash: Attach a diffuser to your flash to spread the light and soften shadows. This is better than direct flash but still not ideal.
* Off-Camera Flash (Recommended): This provides the most control and flexibility.
* Key Light: The primary light source that illuminates the subject.
* Fill Light: A secondary light source used to fill in shadows created by the key light. Often achieved using a reflector or ambient light.
* One-Light Portrait Setups:
* Simple Side Lighting: Place the flash (with a modifier) to one side of the subject, slightly in front of them. This creates dramatic shadows and highlights. Adjust the flash power and distance to control the contrast. A reflector on the opposite side can soften the shadows.
* Loop Lighting: Place the flash slightly to one side and slightly in front of the subject. This creates a small, loop-shaped shadow under the nose. Flattering for most people.
* Rembrandt Lighting: Position the flash so that a triangle of light appears on the cheek opposite the light source. Creates a dramatic and moody look.
* Butterfly Lighting (Paramount Lighting): Place the flash directly in front of the subject, slightly above head height. This creates a butterfly-shaped shadow under the nose. Best for subjects with good skin and symmetrical features.
* Backlighting: Place the flash behind the subject, aiming it towards the camera. This creates a rim light around the subject, separating them from the background. Requires careful exposure and often a reflector to illuminate the front of the subject.
IV. Steps to Capture Fantastic Portraits:
1. Plan Your Shot: Consider the mood and style you want to achieve. Think about posing, background, and lighting.
2. Set Up Your Background: Choose a background that complements your subject and doesn't distract from them. Simple is often best.
3. Position Your Subject: Guide your subject into a pose that is flattering and communicates the desired emotion. Pay attention to their posture, facial expression, and hand placement.
4. Set Up Your Flash and Modifier: Place your flash on a light stand and attach your chosen modifier. Consider the distance to your subject.
5. Camera Settings (Manual Mode is Key):
* Aperture: Controls depth of field. Wider apertures (e.g., f/2.8, f/4) create shallow depth of field, blurring the background and isolating the subject. Narrower apertures (e.g., f/8, f/11) increase depth of field, keeping more of the image in focus.
* Shutter Speed: Controls the amount of ambient light in the image. It doesn't affect the flash exposure (as long as it's below your camera's sync speed). A faster shutter speed will darken the background; a slower shutter speed will brighten it.
* ISO: Keep the ISO as low as possible (e.g., ISO 100) to minimize noise. Only increase it if you need more ambient light and can't lower your shutter speed further.
* White Balance: Set the white balance to Flash or Custom to match the flash's color temperature. If using gels, adjust accordingly.
* Sync Speed: Your camera has a maximum flash sync speed (usually around 1/200th or 1/250th of a second). Don't exceed this speed, or you'll get black bars in your image. High-speed sync (HSS) allows you to use faster shutter speeds, but it reduces flash power.
6. Set Flash Power: Start with a low flash power setting (e.g., 1/16th power) and take a test shot. Adjust the flash power until you achieve the desired exposure.
7. Evaluate Your Test Shot: Check the exposure, shadows, and highlights. Adjust the flash power, distance, and modifier position as needed.
8. Refine Your Pose and Composition: Make small adjustments to the subject's pose and your camera angle to improve the composition.
9. Take the Shot! Focus carefully on the subject's eyes.
10. Chimp and Adjust: Review each shot on your camera's LCD screen. Make further adjustments to the lighting, posing, and camera settings as needed.
V. Tips for Success:
* Practice, Practice, Practice: Experiment with different lighting setups and modifiers to see what works best for you.
* Communicate with Your Subject: Direct them with clear and positive instructions. Help them feel comfortable and relaxed.
* Focus on the Eyes: The eyes are the window to the soul. Make sure they are sharp and well-lit.
* Don't Be Afraid to Experiment: Try different angles, poses, and lighting setups to find your own unique style.
* Learn Post-Processing: Basic post-processing (e.g., exposure adjustments, color correction, sharpening) can enhance your portraits.
Example Scenarios:
* Classic Portrait (Loop Lighting): Off-camera flash with a softbox placed slightly to one side and slightly in front of the subject. Low ISO, aperture around f/2.8-f/4, shutter speed to control ambient light.
* Dramatic Portrait (Rembrandt Lighting): Off-camera flash with a grid spot (to focus the light) placed to one side and slightly behind the subject. Reflector on the opposite side to fill in the shadows. Dark background.
* Outdoor Portrait (Fill Flash): Subject lit by natural sunlight, but with shadows. Off-camera flash with a small umbrella to fill in the shadows. Adjust flash power to balance the flash light with the sunlight.
By understanding the principles of light and practicing different techniques, you can create stunning portraits with just one flash. Good luck!