1. Understanding the Concept:
* The Goal: To capture motion blur from the ambient light while freezing the subject with a flash.
* Ambient Light: Provides the blurred, dreamy, or streaking effects.
* Flash: Provides the sharp focus and proper exposure on your subject. Without the flash, your subject would be blurry as well.
2. Equipment Needed:
* DSLR or Mirrorless Camera: Offers manual control over settings.
* External Flash: Built-in flashes are usually not powerful enough. A dedicated external flash gives you more control over power and direction.
* Tripod (Optional but Recommended): Keeps the background sharp and helps minimize camera shake, especially with slower shutter speeds. If hand-holding, you'll need a steady hand and may need to increase your ISO.
* Lens: Choose a focal length appropriate for your composition (50mm, 85mm, or wider can work).
* Neutral Density (ND) Filter (Potentially): In very bright ambient light, an ND filter will reduce the amount of light entering the lens, allowing you to use even slower shutter speeds.
3. Camera Settings:
* Shooting Mode: Manual (M) or Shutter Priority (Tv or S) mode. Manual mode gives you the most control, but Shutter Priority can be a good starting point.
* Shutter Speed: The key setting. Start with 1/30th of a second and experiment slower from there (1/15, 1/8, 1/4, 1/2, 1 second or slower). The ideal speed depends on the amount of ambient light and how much motion blur you want. The slower the shutter speed, the more blur you'll get.
* Aperture: Choose an aperture based on your desired depth of field (the amount of the image in focus). Typically, f/2.8 - f/5.6 are good starting points for portraits. A wider aperture (smaller f-number) will give you a shallower depth of field (more background blur).
* ISO: Keep the ISO as low as possible (ISO 100-400) to minimize noise. Increase it only if you absolutely need to achieve proper exposure.
* White Balance: Set the white balance based on the ambient light (e.g., Tungsten if indoors with incandescent bulbs).
4. Flash Settings:
* Flash Mode: TTL (Through-The-Lens) or Manual (M). TTL is a good starting point for calculating flash power, while Manual gives you the most consistent results once you dial it in.
* Flash Power: Start with a low power setting (e.g., 1/32 or 1/64) and adjust upwards until your subject is properly exposed by the flash. Remember, the flash is responsible for freezing your subject.
* Flash Position:
* On-Camera Flash (Direct): Can work, but often results in harsh shadows. A diffuser helps.
* Off-Camera Flash (Preferred): Allows for more creative lighting. Use a modifier like a softbox or umbrella to soften the light. You'll need a wireless trigger system (transmitter on camera, receiver on flash). Position the flash at an angle to your subject for more flattering light. Think of Rembrandt lighting or broad lighting techniques.
* Flash Sync Mode: This is crucial. Use Rear Curtain Sync (Second Curtain Sync). This fires the flash at the *end* of the exposure, after the motion blur has been recorded. If you use Front Curtain Sync (First Curtain Sync), the flash will fire at the *beginning* of the exposure, and the blur will appear *in front* of your subject, which usually looks unnatural. Some cameras may label it as Rear Sync, but the idea is the same. Consult your camera manual for how to set this.
5. Composition and Subject Considerations:
* Subject Movement: Encourage your subject to move slightly during the exposure. This can be subtle movements like turning their head, waving their hand, or swaying gently. The amount of movement dictates the length of streaks around them. Too much movement will blur the subject despite the flash.
* Background: Choose a background with interesting light sources (streetlights, neon signs, moving traffic) to create visually appealing motion trails.
* Focus: Focus carefully on your subject's eyes. The flash will freeze them sharply.
6. Step-by-Step Shooting Process:
1. Set up your camera and flash.
2. Compose your shot.
3. Set your aperture and ISO.
4. Determine your desired shutter speed. Start with 1/30th second and adjust based on the ambient light and desired blur.
5. Set your flash power. Start low and increase as needed.
6. Choose Rear Curtain Sync.
7. Focus on your subject's eyes.
8. Have your subject move slightly during the exposure.
9. Take the picture!
10. Review the image and adjust your settings. Fine-tune your shutter speed, aperture, ISO, and flash power until you achieve the desired effect.
7. Important Tips and Troubleshooting:
* Experiment, Experiment, Experiment! This technique requires practice. Don't be afraid to try different settings and subject movements.
* Too Much Ambient Light: If the ambient light is too bright, your background will be overexposed, even with a low ISO. Use an ND filter to reduce the amount of light entering the lens. You can also shoot in lower-light situations, or control the light (e.g. in a studio).
* Subject is Too Blurry: Your shutter speed is too slow, your flash power is too low, or your subject is moving too much. Increase flash power or reduce motion. Slightly increase shutter speed.
* Background is Not Blurry Enough: Slow down your shutter speed.
* Harsh Shadows: Use a diffuser on your flash or use off-camera flash with a modifier to soften the light.
* Camera Shake: Use a tripod. If hand-holding, brace yourself and use a wider stance. Consider increasing your ISO slightly.
* Practice in low light first. This is easier to get the hang of.
Example Scenario:
* Location: City street at dusk
* Camera: DSLR
* Lens: 50mm f/1.8
* Camera Settings:
* Mode: Manual
* Aperture: f/2.8
* ISO: 200
* Shutter Speed: 1/15 second
* White Balance: Tungsten
* Flash Settings:
* Mode: TTL
* Power: 1/16 (starting point, adjust as needed)
* Position: Off-camera, to the side of the subject, with a small softbox
* Sync Mode: Rear Curtain
* Subject: Standing still, but instructed to turn their head slightly during the exposure.
By following these steps and experimenting with your settings, you can create stunning and unique long exposure portraits that capture motion and mood. Good luck!