Photoshop Special Effects - Masking
This is called masking and can be done in a variety of ways. One method is called the "quick mask mode". This is quick and easy to do and results are typically acceptable.Quick masking:
Locate the button called "edit in quick mask mode" in Adobe Photoshop. It is located near the bottom of the main tool bar and appears as a circle in a rectangle. There"s also a short-cut key: Q. Once in quick mask mode, you can select and deselect areas by painting them with white and black respectively, using the standard brush tool.
Zoom to 100 or 200 % for best precision. A soft-edged brush can be used to avoid hard edges. When done, exit the masking mode and go to "Select > Feather" and set the feather radius somewhere in the range of 5-10 pixels. A nice feature is that you can set the opacity to anywhere between 0 and 100%, allowing you to apply the effect stronger or weaker in one part of the image than another.
Layer masking:
Somewhat more complicated, you can add a layer mask. This permits you to apply any effect gradually from any point in your photo. Follow these steps in Photoshop:
1. Select "Windows > Layers".
2. Right click on your layer and choose "Duplicate layer".
3. Click on the little icon in the bottom of the layer box called "Add layer mask".
4. Choose the "Gradient tool" on the main tool box.
5. Select a gradient style from the top "Options" bar (linear, radial etc.).
6. Click on your image on the point you don"t want to change, and drag the mouse away to the point where you want the full effect to take place. The effect will be applied gradually more and more along this line you"ve now created.
7. Last, return to your original background layer and apply any effect you want. This will apply the effect in a soft, gradual way. Use opacity to turn the effect down to less than full strength if you want.
Lens-like effects:
Using the same layer masking explained from above, you can apply "Gaussian blur" which will make the selected areas appear soft-focused, a bit like if you had used a large-aperture lens. With "Curves" you can make your corners darker than the center, replicating the lens effect called vignetting.
In principle, vignetting is considered a lens dysfunction, but subjectively it can add an extra feeling to your photo. It will create a kind of frame that will have a "sucking" effect, drawing more focus to the center of your photo. You can also just lower the contrast and/or color-saturation around your main subject, helping to divide it from the background clutter. Be creative with the many options you have available.