Understanding the Goal
The idea is to isolate the subject (the person in the portrait) from the background. Once isolated, we can apply a blur effect *only* to the background, creating a shallow depth-of-field look, which is a common portrait photography technique.
Step-by-Step Guide
1. Open Your Image in Photoshop: Start by opening the portrait image you want to edit in Photoshop.
2. Duplicate the Background Layer (Important!):
* In the Layers panel (usually on the right side of your screen), you should see your image layer, typically named "Background."
* Right-click on the "Background" layer and select "Duplicate Layer." This creates a copy of your image. Working on a copy allows you to preserve the original in case of mistakes. Name the duplicate layer something descriptive, like "Subject and Background" or "Layer 1."
3. Select the Magnetic Lasso Tool:
* In the Tools panel (usually on the left side of your screen), locate the Lasso Tool. It looks like a lasso.
* Click and *hold* on the Lasso Tool icon. A fly-out menu will appear. Select the Magnetic Lasso Tool.
4. Adjust Magnetic Lasso Tool Settings (Crucial for Good Results):
* Look at the Options Bar at the top of the screen. You'll see settings for the Magnetic Lasso Tool. These settings are *critical* to getting a good selection. Here's what each does and suggested starting points (adjust as needed for your image):
* Width: This controls the range (in pixels) that the tool searches for an edge. A higher width means it looks further away from your cursor, but too high and it might grab the wrong edges. Start with 5-10 pixels. Increase it if you're having trouble sticking to the edge; decrease it if it's sticking to the wrong thing.
* Contrast: This determines how sensitive the tool is to changes in contrast along the edge. If your subject has a very clear outline, you can use a higher contrast value. If the edge is blurry or poorly defined, lower the contrast. Start with 10-20%.
* Frequency: This controls how often Photoshop places anchor points along your selection. More points mean a more accurate selection, but also a more complex path. Start with 50-60. Increase it if the line deviates from the edge; decrease it if you're getting too many points.
* Tablet Pressure to Size: Leave this unchecked for consistent performance.
5. Make Your Selection:
* Click anywhere on the *edge* of the subject you want to select. This will create your starting anchor point.
* Carefully trace the outline of your subject. Move your mouse slowly and steadily along the edge. The Magnetic Lasso Tool will automatically try to "snap" to the edge based on the settings you chose.
* If the tool misplaces an anchor point:
* Press the Delete key (or Backspace on Mac) to remove the last anchor point. Then, reposition your cursor and continue tracing.
* If you need to manually place an anchor point:
* Click the mouse button at any point along the edge. This forces the tool to create an anchor point at that specific location. This is useful if the automatic edge detection is failing.
* Zoom In: Use the Zoom tool (magnifying glass) to zoom in for precise selection along difficult edges (hair, fabric folds, etc.). Use `Ctrl/Cmd` + `+` to zoom in, `Ctrl/Cmd` + `-` to zoom out.
* Complete the Selection: When you've traced all the way around your subject, move your cursor back to the starting anchor point. A small circle will appear next to the cursor. Click to close the selection. You should now see a "marching ants" outline around your subject.
6. Refine the Selection (Important!): The Magnetic Lasso is good, but rarely perfect. Use "Select and Mask" to refine your selection.
* Go to Select > Select and Mask... in the top menu.
* The "Select and Mask" workspace will open. Here are key settings:
* View Mode: Choose an overlay view (e.g., "Overlay" or "On Layers") to easily see what is selected and unselected. Adjust the "Opacity" slider to make the overlay easier to see.
* Global Refinements:
* Smooth: Helps to smooth out jagged edges. Start with a small value (e.g., 1-2) and increase as needed.
* Feather: Softens the edges of the selection, which helps to blend the subject into the blurred background. Start with a small value (e.g., 0.5 - 1 pixel). A feather is usually desirable.
* Contrast: Increases the contrast of the edge. Use with caution, as it can sometimes create harsh lines.
* Shift Edge: A negative value shrinks the selection; a positive value expands it. This is useful if you've accidentally included too much of the background or cut off part of the subject.
* Refine Edge Brush Tool (the most important tool here): This allows you to refine the selection, especially around tricky areas like hair.
* Select the Refine Edge Brush Tool (looks like a brush with a hair strand).
* Paint along the *edge* of the subject, particularly around hair, fur, or other fine details. Photoshop will analyze the pixels you're painting over and try to better identify the subject's edge. You may need to adjust the brush size (using the `[` and `]` keys). Zoom in for accuracy.
* Output Settings:
* At the bottom of the Select and Mask panel, find the "Output To" dropdown menu. Choose "New Layer with Layer Mask". This is crucial! It will create a new layer containing only your selected subject, with a mask controlling its visibility.
* Click "OK".
7. Blur the Background:
* In the Layers panel, you should now have a new layer (e.g., "Subject and Background copy 2") *above* your original "Subject and Background copy" layer. The new layer shows just your subject; the layer below it contains the original entire image.
* Select the "Subject and Background copy" layer (the one containing the full image, *not* the new layer with the mask). This is the layer we'll blur.
* Go to Filter > Blur > Gaussian Blur...
* Adjust the Radius slider to control the amount of blur. A small radius (e.g., 2-5 pixels) creates a subtle blur, while a larger radius creates a more dramatic effect. Experiment to find the look you want. Keep an eye on the blur amount, you don't want it to look unnatural.
* Click "OK".
8. Optional: Fine-Tune the Mask:
* If you notice any issues with the mask (e.g., areas where the background is visible around the subject), you can edit the mask directly:
* In the Layers panel, click on the layer mask thumbnail next to the subject's layer. The mask thumbnail is the black and white rectangle.
* Select the Brush Tool (B).
* Set your foreground color to Black to *hide* areas of the layer (i.e., reveal more of the blurred background).
* Set your foreground color to White to *reveal* areas of the layer (i.e., show more of the subject).
* Paint on the image where you need to adjust the mask. Use a soft-edged brush and low opacity for subtle adjustments.
9. Optional: Add Vignetting:
* Create a new empty layer above all other layers (Layer > New > Layer...).
* Select the Elliptical Marquee Tool.
* Drag an ellipse that covers the majority of the image, leaving some space at the edges.
* Go to Select > Inverse. This selects everything *outside* the ellipse.
* Choose a dark color (like a dark gray or black) as your foreground color.
* Press Alt+Delete (or Option+Delete on Mac) to fill the selected area with the dark color.
* Change the layer blend mode to Multiply and reduce the layer opacity to around 10-30% to create a subtle vignetting effect.
10. Save Your Work:
* Go to File > Save As...
* Save your image as a Photoshop (.PSD) file to preserve the layers and allow you to edit it later. You can also save a flattened copy as a JPEG or PNG for sharing.
Important Tips for Success:
* Zoom In: Work at high zoom levels (200-400%) for detailed accuracy.
* Patience: Take your time when tracing the subject's outline. The more accurate your selection, the better the final result will be.
* Experiment with Settings: Don't be afraid to adjust the Magnetic Lasso Tool settings (Width, Contrast, Frequency) and the Gaussian Blur radius to find what works best for your image.
* Use a Graphics Tablet: If you have a graphics tablet, it can make creating selections much easier and more natural.
* Non-Destructive Editing: Always work on a copy of your original image. Using layer masks is a non-destructive way to hide or reveal parts of a layer without permanently deleting them.
* Alternative Tools: Consider using other selection tools for more complex selections:
* Quick Selection Tool: Good for quickly selecting areas of similar color and tone.
* Object Selection Tool: Photoshop tries to automatically identify and select objects in the image. Great for initial selection.
* Pen Tool: Creates precise vector paths, which can be converted into selections. The most accurate selection tool, but requires practice.
* Practice: Like any skill, creating good selections in Photoshop takes practice. Experiment with different images and techniques to improve your skills.
By following these steps and practicing, you'll be able to effectively blur the background of your portraits and create professional-looking results. Remember to experiment and have fun!