Key Concepts:
* Depth of Field (DOF): The area in your image that appears sharp. A shallow depth of field means only a small portion of the image is in focus (your subject), while the rest is blurred. A deep depth of field means more of the image, both near and far, is sharp. We want a shallow DOF for blurred backgrounds.
* Aperture: The opening in your lens that allows light to pass through to the camera sensor. It's measured in f-stops (e.g., f/1.4, f/2.8, f/8, f/16). *Lower* f-numbers (e.g., f/1.4, f/2.8) represent *wider* apertures, which create a shallower depth of field and more background blur. *Higher* f-numbers (e.g., f/8, f/16) represent *narrower* apertures, which create a deeper depth of field and less blur.
* Focal Length: The distance between the lens and the image sensor when the subject is in focus. Measured in millimeters (mm). Longer focal lengths (e.g., 85mm, 135mm, 200mm) generally create more background blur than shorter focal lengths (e.g., 24mm, 35mm, 50mm) when used at the same aperture and subject distance.
* Distance: The distance between:
* Camera and Subject: The closer you are to your subject, the shallower the depth of field and the more blurred the background will be.
* Subject and Background: The further your subject is from the background, the blurrier the background will become.
Steps to Achieve Blurred Backgrounds:
1. Use a Wide Aperture:
* Set your camera to Aperture Priority (Av or A) mode. This allows you to control the aperture while the camera automatically adjusts the shutter speed to achieve the correct exposure.
* Choose the lowest f-stop number your lens allows (e.g., f/1.4, f/1.8, f/2.8, f/4). The lower the number, the wider the aperture, and the shallower the depth of field.
* Important Note: Using very wide apertures like f/1.4 or f/1.8 requires precise focusing, as the in-focus area is very narrow. Use single-point autofocus and carefully place the focus point on your subject's eye (the eye closest to the camera).
2. Use a Longer Focal Length:
* Lenses with longer focal lengths (e.g., 85mm, 135mm, 200mm) naturally compress the background and create more blur than wider lenses (e.g., 24mm, 35mm, 50mm), *all other factors being equal*.
* If you're using a zoom lens, zoom in to the longest focal length appropriate for your composition.
3. Position Your Subject Farther from the Background:
* The further your subject is from the background, the more blurred the background will appear. Put as much distance as possible between your subject and any distracting elements in the background.
4. Get Closer to Your Subject:
* The closer you are to your subject, the shallower the depth of field. This means more background blur.
* Be mindful of minimum focusing distances. Every lens has a minimum distance at which it can focus. If you get too close, your subject will be out of focus.
5. Choose a Lens Designed for Portraiture:
* Lenses specifically designed for portrait photography often have wide maximum apertures (e.g., f/1.4, f/1.8) and desirable focal lengths (e.g., 50mm, 85mm, 135mm). These lenses are optimized for creating beautiful background blur. Common choices include:
* 50mm f/1.8 ("Nifty Fifty"): Affordable and versatile, great for beginners.
* 85mm f/1.8 or f/1.4: A classic portrait lens, known for flattering perspectives and beautiful bokeh.
* 135mm f/2: Excellent for compressing the background and creating very creamy bokeh.
6. Consider Background Elements:
* While blurring the background helps, the *quality* of the background also matters. Points of light (e.g., sunlight filtering through trees, city lights) will turn into pleasing bokeh "bubbles" when blurred. Avoid distracting elements with sharp lines or bright colors, even when blurred, as they can still be distracting.
7. Use ND Filters (Optional):
* If you are shooting in bright sunlight with a wide aperture (e.g., f/1.4) your image may become overexposed, even at the fastest shutter speed. A Neutral Density (ND) filter reduces the amount of light entering the lens, allowing you to use a wide aperture in bright conditions without overexposing the image.
Example Scenario:
Let's say you want to take a portrait of a friend in a park. Here's how you might apply these techniques:
1. Lens: Use an 85mm f/1.8 lens.
2. Camera Mode: Set your camera to Aperture Priority (Av or A) mode.
3. Aperture: Choose f/1.8.
4. Positioning:
* Have your friend stand a good distance away from any trees, buildings, or other distracting elements in the background.
* Position yourself relatively close to your friend (within the lens's minimum focusing distance, of course).
5. Focus: Use single-point autofocus and carefully focus on your friend's eye closest to the camera.
6. Shoot: Take the photo. You should see a shallow depth of field with your friend in sharp focus and a pleasingly blurred background.
Troubleshooting:
* Image is too bright (overexposed):
* Reduce the aperture (increase the f-stop number, e.g., from f/1.8 to f/2.8).
* Increase the shutter speed (the camera does this automatically in Aperture Priority mode, but you can check it).
* Lower the ISO.
* Use an ND filter.
* Image is too dark (underexposed):
* Increase the aperture (decrease the f-stop number, e.g., from f/2.8 to f/1.8).
* Decrease the shutter speed (be careful not to go too low, or you'll get motion blur).
* Increase the ISO.
* Subject is not in focus:
* Make sure you are within the lens's minimum focusing distance.
* Use single-point autofocus and carefully place the focus point on the subject's eye.
* Check that your focus mode is set correctly (e.g., single autofocus for stationary subjects, continuous autofocus for moving subjects).
* Background is not blurred enough:
* Use a wider aperture (lower f-stop number).
* Use a longer focal length lens.
* Get closer to your subject.
* Move your subject farther away from the background.
Practice:
Experiment with different aperture settings, focal lengths, and distances to see how they affect the depth of field and the amount of background blur. The more you practice, the better you'll become at achieving the desired results.