Composting Part Two

There are as many ways to composite images in Photoshop as there are people who composite images. After a while, you will develop a set of tools and tricks that you will use repeatedly. For now, we’ll discuss a few more advanced compositing techniques, which will help you produce more convincing images. These may or may not be relevant to your specific application, but they should serve as a useful point of departure as you’re working on your images.

Using Filters

Filters can be very useful tools in compositing. However, it’s very easy to over-use filters: they’re among the top causes of ‘bad photoshop.’ There are a few that are useful in our specific case, however. One of the big problems you’ll run into as you try to make a digital photograph resemble an image you’ve scanned is the grain of the images. Grain means the fine texture of the image, when you’ve zoomed in very close. Mass-produced images printed on an offset press have what’s called a Moire pattern- it’s the fine distribution of dots you’ll see when zoomed in very close. Digital photos look much smoother when you zoom in. Here’s a useful process for making the grain match slightly better:

With the background layer selected, go to Filters: Blur. Select Gaussian Blur, and input a radius between 1 and 2 pixels (see what works best for your image). This should smooth out the Moire pattern, but it leaves a soft, undefined quality in the image. To fix this, go to Filters: Sharpen: Unsharp Mask. Use these settings: Amount: 20 %, Radius: 50 pixels, Threshold: 0 levels. This should get you close, and help sharpen up your softened background.

Another possible method is to add grain to your digital images. To do this, select the layer with your digital image on it. Go to Filter: Noise: Add Noise. Start with a small amount (10% or so) and use Gaussian distribution. You’ll see this adds some grit to your image. Working on both the background and foreground, you can obtain a fairly close match in grain.

More Useful Tools

There are a few more tools in the Toolbar that can help with compositing. First off, I’ll cover some more advanced settings for the Clone Stamp tool.

With the Clone Stamp tool selected, click on the Brush menu in the Control Panel at the top of the window. The two main things to play with here are the size and hardness of the brush. If you’re doing a fairly extensive cleanup process, my general principle is to start with the brush small and hard, and fully opaque (you can adjust opacity in Control Panel as well. Once you’ve gotten the rough work done, decrease the hardness of the brush, increase the size, and drop the opacity. This will allow you to smooth out and blend your copied area into the image. This process is particularly useful if you have to remove the ‘gutter’ of a book from the center of your scanned image.

Burn and Dodge Tools

The Dodge tool looks like a black version of the Zoom tool. It’s used to lighten an area of an image. It’s useful for opening up dark areas in your composited image. Use it carefully: make sure your brush is set rather soft, and start carefully, with Exposure around 50%. Notice that it lightens the area quickly: the trick is getting an even-looking lightened effect.

The Burn Tool is the opposite of the Dodge Tool- it darkens an area of your image. This is useful for adding shadows to your composited image. Use it the same way as the Dodge Tool, but again, go easy at first. It’s located under the Dodge Tool in the flyout menu.

Blur, Sharpen and Smudge

These tools work similarly to the Burn and Dodge tools, but do slightly different things: rather than darkening or lightening an area, they blur or sharpen the area slightly. This is useful for adjusting edges of a composited image, to make them clearer or softer and help blend them into the background. Again, start with Strength around 50%, and adjust as needed.

Using the Transform Tools

We briefly mentioned the Transform tools in the Edit menu, but they bear a bit more discussion. Many of them function similarly, but the Scale tool is the most commonly useful, followed by Perspective and Warp. The Perspective tool is particularly handy if you want to adjust the way your composited elements ‘sit’ in the image: it allows you to tweak how the image sits in a one-point perspective plane. Warp works by creating a grid of ‘handles’ over the image: grab any one of them to distort that portion of the image.

Use Scale and Warp carefully though: if you blow something up much larger than it originally was, you can end up with a pixilated image. Generally, to use the Transform tools, select the layer you’d like to transform, go to Edit: Transform, pick the type of transformation you’d like to use, then adjust the image using the handles which appear around it. If you don’t like your transformation, click outside your image, and a dialog box will ask whether you’d like to apply the transformation. Click ‘no’, and your image will revert to its original state. You can do the same to apply a transformation, or you can simply double-click on the image.