Understanding the Process
The general idea is to:
1. Select the Subject: Use the Magnetic Lasso Tool to carefully select the person in the portrait.
2. Invert the Selection: This selects the background instead of the subject.
3. Apply a Blur: Use a blur filter (like Gaussian Blur) to blur the selected background.
Step-by-Step Instructions
1. Open Your Image in Photoshop:
* Launch Photoshop.
* Go to `File > Open` and choose your portrait image.
2. Select the Magnetic Lasso Tool:
* In the Toolbar (usually on the left side of your screen), find the Lasso Tool icon. It looks like a lasso rope.
* Click and hold the Lasso Tool icon. A flyout menu will appear.
* Select the Magnetic Lasso Tool.
3. Configure the Magnetic Lasso Tool (Important):
* Look at the options bar at the top of the screen (under the menu bar). Adjust these settings:
* Width: This controls how far the tool will search for the edge. A smaller value (e.g., 3-5 pixels) is good for complex edges. Larger values (e.g., 10-20 pixels) are suitable for simpler, more defined edges. Adjust this as needed depending on your image. Start small and increase if the tool struggles.
* Contrast: This controls how sensitive the tool is to changes in color and brightness. A higher contrast value (e.g., 10-20%) will help it stick to sharper edges. If the edges are blurry or soft, lower the contrast.
* Frequency: This controls how often the tool places anchor points along the selection path. A higher frequency (e.g., 50-70) will create a more detailed selection, but it can also make the selection process slower. Lower frequency (e.g., 20-30) for smoother edges.
* Feather: Leave this at 0 for now. We'll add feathering later if needed.
4. Start Selecting the Subject:
* Click on the edge of the person you want to select. This sets your starting point.
* Slowly move your mouse cursor along the edge of the person. The Magnetic Lasso Tool will automatically try to snap to the edge.
* Click manually to place an anchor point:
* When you reach a sharp corner.
* When the tool is having trouble finding the edge.
* To remove a misplaced anchor point: Press the `Delete` or `Backspace` key.
* To switch to the regular Lasso Tool temporarily: Hold down the `Alt` (Windows) or `Option` (Mac) key. This lets you draw a freehand selection if the Magnetic Lasso is really struggling. Release the key to go back to the Magnetic Lasso Tool.
* Zoom In! Use `Ctrl + +` (Windows) or `Cmd + +` (Mac) to zoom in for more precise selections, especially around hair or intricate details. Use the Hand Tool (press the `H` key) to move around the image when zoomed in.
5. Close the Selection:
* Continue tracing around the person until you reach your starting point.
* When you are near the starting point, the cursor will change to include a small circle.
* Click on the starting point to close the selection. A dotted line (marching ants) will appear around the selected subject.
6. Refine the Selection (Optional but Recommended):
* Go to `Select > Select and Mask` (or click the "Select and Mask" button in the options bar). This opens a dedicated workspace for refining selections.
* Use the tools in the "Select and Mask" workspace to improve the selection:
* Refine Edge Brush Tool: This tool (often represented by a brush icon with a plus sign) is especially useful for hair. Brush over the edges of the hair to refine the selection and include stray hairs.
* Brush Tool: Use the regular Brush Tool (with a hardness appropriate for the edge) to add or subtract from the selection manually. Make sure you've selected the correct mode (Add or Subtract) in the options bar.
* Global Refinements: Adjust the "Smooth," "Feather," "Contrast," and "Shift Edge" sliders to further improve the selection.
* Output Settings: In the "Output Settings" section at the bottom of the panel, set the "Output To" option to "Selection."
* Click "OK" to apply the changes and return to the main Photoshop workspace.
7. Invert the Selection:
* Go to `Select > Inverse` (or press `Shift + Ctrl + I` (Windows) or `Shift + Cmd + I` (Mac)). This switches the selection to the *background* instead of the person.
8. Apply the Blur:
* Go to `Filter > Blur > Gaussian Blur`.
* In the Gaussian Blur dialog box, adjust the Radius slider to control the amount of blur. A small radius (e.g., 2-5 pixels) will create a subtle blur, while a larger radius (e.g., 10-20 pixels or more) will create a more dramatic blur.
* Preview: The dialog box shows a preview of the blur. Experiment with the radius until you achieve the desired effect.
* Click "OK" to apply the blur.
9. (Optional) Add Feathering to the Selection Before Blurring:
* Sometimes, a harsh edge between the subject and the blurred background can look unnatural. To prevent this:
* After inverting the selection (Step 7), go to `Select > Modify > Feather`.
* Enter a small feather radius (e.g., 1-3 pixels). The appropriate value depends on the resolution of your image.
* Click "OK".
* *Then* apply the Gaussian Blur.
10. (Optional) Adjust Blur Amount in Different Areas:
* If you want to blur some parts of the background more than others, you can use a layer mask.
* Duplicate the Layer: In the Layers panel, right-click on your original layer and choose "Duplicate Layer."
* Apply Blur to the Duplicated Layer: Repeat Steps 7 and 8 on the *duplicate* layer, applying a *stronger* blur than before.
* Add a Layer Mask: Click the "Add Layer Mask" button at the bottom of the Layers panel (it looks like a rectangle with a circle inside). A white rectangle will appear next to the layer thumbnail.
* Paint on the Layer Mask:
* Select the Brush Tool (press the `B` key).
* Set your foreground color to black.
* Choose a soft, round brush.
* Paint on the layer mask over the areas where you *don't* want the strong blur. Painting with black on the mask hides the stronger blur, revealing the less-blurred layer underneath.
* If you make a mistake, switch the foreground color to white and paint to reveal the stronger blur again.
11. Deselect:
* Go to `Select > Deselect` (or press `Ctrl + D` (Windows) or `Cmd + D` (Mac)) to remove the selection outline.
12. Save Your Image:
* Go to `File > Save As...` and choose a file format (e.g., JPEG, PNG, TIFF).
* Give your file a name and click "Save."
Tips for Success:
* Zoom In: Don't try to make selections without zooming in. Precision is key.
* Take Your Time: Rushing will result in a sloppy selection.
* Experiment with Settings: The best settings for the Magnetic Lasso Tool will vary depending on the image.
* Practice: The more you use the Magnetic Lasso Tool, the better you'll get at it.
* Use a Graphics Tablet: If you have a graphics tablet (like a Wacom), it can make selections easier and more natural.
* Non-Destructive Editing: Consider working on a copy of your original image or using adjustment layers to avoid permanently altering the original pixels.
Alternatives to the Magnetic Lasso Tool:
While the Magnetic Lasso Tool is useful, you might also consider these alternatives:
* Quick Selection Tool: Good for quickly selecting large areas with relatively defined edges.
* Pen Tool: Provides the most precise control for creating complex selections, but it takes more practice to master.
* Object Selection Tool: (Newer versions of Photoshop) Often very effective at automatically selecting objects, making the initial selection faster.
Good luck!