1. Understanding the Concept: Overexposure
The key to a pure white background is to overexpose it. This means making the background so bright that it loses detail and renders as pure white in your final image. However, you need to do this without blowing out your subject.
2. Essential Equipment:
* Camera: Any camera with manual controls (aperture, shutter speed, ISO) will work.
* Lens: A lens suitable for your subject (e.g., macro lens for small objects, portrait lens for people).
* Lights (2-3):
* Two Lights for the Background: These are crucial. Strobe flashes (speedlights or studio strobes) are ideal because they provide a powerful, controllable burst of light. Constant lights (LED panels, etc.) can work, but you'll likely need more powerful ones.
* One Light for the Subject (Optional): You might need a separate light for your subject if the background lights aren't illuminating it adequately.
* White Background:
* Seamless Paper: The most common and versatile option. Avoid wrinkles or creases.
* White Muslin Cloth: Can be used, but prone to wrinkles. Requires careful ironing.
* White Wall: Works if you have a perfectly white, smooth wall.
* White Acrylic Sheet: Great for reflective surfaces and product photography.
* Light Stands: To position your lights.
* Light Modifiers (Optional but Recommended):
* Softboxes: Diffuse the light for a softer, more even illumination on your subject.
* Umbrellas: Another way to diffuse light. Less precise than softboxes but cheaper.
* Barn Doors: To control the spill of light.
* Gels: To add color to the background, if desired (for creative effects).
* Light Meter (Optional but Helpful): A light meter will give you precise readings for accurate exposure. Your camera's built-in meter can also be used, but it's less reliable for this specific technique.
* Tripod: To keep your camera steady, especially when using slower shutter speeds.
3. Setting Up Your Scene:
1. Position the Background: Place the white background behind your subject. Ensure it's smooth and free of wrinkles. If using seamless paper, make sure it curves smoothly from the vertical background to the horizontal surface.
2. Place the Subject: Position your subject a reasonable distance *away* from the background. This distance is important to allow you to light the background separately without affecting the subject too much (and vice versa, helps control the background light's spill onto the subject).
3. Position the Background Lights: Place one light on either side of the background, angled towards the center of the white surface. These lights are *exclusively* for illuminating the background. Ensure they are positioned so that the light spread is as even as possible.
4. Position the Subject Light (If Needed): If the background lights aren't providing enough illumination on your subject, place a separate light in front of your subject. Use a modifier like a softbox to soften the light.
5. Camera Position: Position your camera on a tripod, facing the subject.
4. Camera Settings and Exposure:
1. Set your camera to Manual (M) mode. This gives you complete control over aperture, shutter speed, and ISO.
2. Start with your aperture: Choose an aperture that gives you the desired depth of field. For product photography, a narrower aperture (f/8, f/11, or even higher) is often used to ensure everything is in focus. For portraits, a wider aperture (f/2.8, f/4) can be used for a shallow depth of field.
3. Set your ISO: Start with the lowest possible ISO (usually ISO 100) to minimize noise.
4. Turn off Auto-ISO. You want complete control.
5. Turn off Automatic White Balance. Set white balance to a specific setting (Daylight, Flash, Custom) that is appropriate for your lighting. Using a custom white balance measured off a grey card can be very helpful.
6. Power on your strobes and set them to a low power. (If using constant lights, turn them on.)
7. Adjust Shutter Speed and Background Lights for the White Background: This is the key step. Increase the power of your background lights and/or adjust your shutter speed until the *background* is significantly overexposed (about +2 to +3 stops over). Use your camera's histogram to monitor this. You want the right edge of the histogram to be clipping (hitting the right edge), indicating pure white. Take a test shot and review the histogram. Increase or decrease background light power (or shutter speed) to achieve this clipping of the highlights on the right side of the graph.
8. Adjust Subject Light for Correct Exposure on Subject: Now, adjust the power of your subject light (if you're using one) until your subject is properly exposed. Use your camera's meter or a handheld light meter to help. Aim for a neutral exposure on your subject (0 stops). Again, check the histogram to make sure your subject's highlights are not clipping.
5. Tips and Troubleshooting:
* Histogram is Your Friend: The histogram is your most valuable tool for judging exposure. Aim for the right edge of the histogram to be clipped for the background, but *avoid* clipping the highlights on your subject.
* Test Shots are Crucial: Take lots of test shots and review them carefully on your camera's LCD. Zoom in to check for blown highlights or unwanted shadows.
* Distance is Key: The distance between the subject and the background, and between the lights and the background, is important. Experiment to find the sweet spot where you can overexpose the background without significantly affecting the subject.
* Light Modifiers Make a Difference: Softboxes and umbrellas will give you much more even and flattering light on your subject.
* White Balance: Getting your white balance right is important to avoid color casts. Use a gray card to set a custom white balance.
* Avoid Shadows: Ensure the background lights are positioned to eliminate any shadows cast by the subject onto the white background.
* Cleanliness: A perfectly white background will show every speck of dust. Clean your background regularly!
* Pay Attention to Reflections: If you're shooting reflective objects, be mindful of what's reflecting in them. Adjust your lighting and camera position to minimize unwanted reflections.
* Post-Processing (Minimal): While the goal is to get it right in camera, minor adjustments to brightness, contrast, and white balance in post-processing (e.g., Photoshop, Lightroom) can further refine the image.
In summary, creating a pure white background in camera is about carefully controlling the light and overexposing the background without overexposing your subject. Practice and experimentation are key to mastering this technique.