This week, we will discuss the basics of capturing digital images on Macs, as well as beginning to composite images. You will need to shoot a few digital images to composite into your scanned images. This can be done with any digital camera that provides high-enough resolution- even your phone if you can make that work. If you don’t have access to any form of digital camera, there are digital cameras that can be checked out from the Library.
At this point, we aren’t going to get too involved with techniques for shooting digital photographs- just set your camera to Auto mode and point-and-shoot. If you have more experience with digital photography, feel free to shoot however you’d like, but don’t feel like you need special photo skills to complete the assignment. One tip: If you can set resolution on your digital camera, set it as high as possible, and shoot in TIFF mode if you can.
Once you have your images on your camera, the next trick is getting them onto your computer. The technique for doing this varies depending on the camera, but the principle remains the same: your camera functions like a remote hard drive (like your thumb drive) from which you can select and copy files to your computer.
If you have a dock, or another system for capturing images, go ahead and use it. If not, most digital cameras have a USB adapter cord. These instructions are based on using a USB cord and the Mac program Image Capture.
Here’s what you do:
1) Make sure your camera is turned off.
2) Connect the USB cord to your camera and your computer.
3) Turn on the camera.
4) Go to Macintosh HD/Applications/Image Capture, and start Image Capture
5) In the dialog box, select Download Some
6) Choose the folder you’d like to download to (Desktop is fine)
7) Select the images you’d like to download, and click Download.
Beginning Compositing
Now, I’d like to start discussing the basics of compositing images. First, we’ll go over the basic areas in the Photoshop window. They are as follows:
1) Across the top, we have the drop-down Menu area. Each of these menus has many options associated with it: generally they are global commands that affect the entire image.
2) On the left side of the screen is the Toolbar. Tools from the Toolbar are generally used to select or change only a portion of an image.
3) Underneath the Menu area is another palette: this changes based on the tool you select from the Toolbar. Generally, the items here will give you more control or allow you to access special features of the tool you’re using.
4) On the right, you will find a selection of palettes. You can customize the palettes displayed here by going to Window and selecting the palette you’d like. For now, go to Window: Layers and make sure your Layers palette is visible- we’ll be using this a lot as we start to edit.
5) In the center you will find your image. Note that there is some additional information displayed around it: the file size, the level of Zoom you are currently set to, etc.
Compositing images in Photoshop is a complex task with many subtleties. It’s a bit more of an art than a science, but we’ll cover some of the basic principles to make compositing easier. First, we’ll go over some basic adjustments and cleanup for your scanned images- it’s easier to composite if you start with a good image.
Basic Image Cleanup
After you’ve finished rotating and cropping your background image, the first thing to do is get it to print size. Don’t ever start working on a composite without knowing the print size: knowing your print size tells you how big your finished image needs to be, and can save you a lot of unnecessary work. Generally, if the image looks OK when you’re zoomed in to 100% in Photoshop, it should look OK printed, in terms of resolution and composited effects. Color is another matter entirely, but we will discuss this later.
So, go to Image: Image Size and size your image to the largest dimensions that will fit on an 8.5x 11” sheet of paper (leave yourself about a ½” margin all around), and reduce your resolution to 300 dpi. You should already have these saved as 300dpi PSD files, with 10” as the longest dimension.
If your scanned image is rotated oddly, here’s a handy trick to get it perfectly aligned. Find a line which should be horizontal. Grab the Ruler tool from the Toolbar (it lives behind the Eyedropper, in the flyout menu). Draw a line with the Ruler over the line you’d like to be horizontal. Then, go to Image: Adjustments: Rotate Canvas: Arbitrary. In the rotate menu, the number of degrees you’ll need to rotate to make your line horizontal will pop up. Hit OK. Once this is done, you’ll need to crop the image. Grab the Crop tool, make sure all your values in the menu bar are empty, and crop out any white space which shows up after rotating.
The Layers Palette
You’ll be doing a lot of work with the Layers palette as you’re starting to composite in Photoshop, so let’s take a minute to look at it. You should just have one layer at this point, labeled “Background.” Layers in Photoshop allow you to ‘stack’ images to create a finished image. Layers in the Layers palette are arranged from the top down- so the top layer in the Layers palette is the top layer in your image. If you can’t see something in your image, the arrangement of your layers is the first thing to check.
To make a new layer (with nothing on it), click on the little page of paper at the bottom of the Layers palette. You can also rename layers if you’d like. Clicking and dragging layers allows you to change the order of layers. Finally, clicking on the eye next to a layer hides its contents- so you can ‘turn off’ a layer if you don’t want to see it.
The big thing to remember with layers is that you can only edit one layer at a time. If Photoshop won’t let you edit part of an image, it’s probably because it’s not on the layer you’ve selected. This is really important, and can get confusing fast. So, make a habit of naming your layers right away- so you can click on the Astronaut layer when you want to edit the Astronaut, for example.
As a first step, go to Select: Select All, then Edit:Copy your image. Go to File: New. This will make a new document which is the same size as your image. Go ti Edit: Paste. This will place your image on a new layer in your new file. This is now your working canvas. This allows you to edit your background more easily- unless it’s copied, you can’t move it around.
General Image Corrections
1) In the Image: Adjustments menu, you will find a large number of adjustment controls for your entire image. Say you don’t like the colors, or the contrast, or would like increase the saturation- you can do all of these things here. At this point I’m more interested in familiarizing you with the options, than giving all the really technical details- play with these if you’d like. If you don’t like something, you can always hit Command-Z and undo it.
Some Useful Tools
In the Toolbar, there are several tools that are useful to know right off the bat. Always remember: if there’s a little arrow at the lower left of a tool, click and hold down on it for more tools hiding underneath it. We will discuss a few more of these tools next week.
1) The Move Tool. This is the top tool on the menu, with an arrow. You can move objects back and forth in the varied layers. Just select the layer, and click + drag, or use your keyboard arrow keys to move objects around. Remember: you can only move objects on the active layer. Select the layer with the object you’d like to move before moving it.
2) The Lasso Tools. These are great for selecting and copying an area of an image. They work slightly differently- the regular Lasso tool just lets you draw an area to select, but the Polygonal Lasso works well for outlining objects, as you can click on a series of points to outline the object. The Magnetic Lasso is good for isolating people or objects- it ‘snaps’ to edges of color variation. Use it carefully.
3) The Healing Brush tool. This looks like a band-aid. The Healing Brush eliminates small defects or spots in an image by sampling the pixels around the point you want to clean up. In order to use it, hold down Option and click a ‘good’ area of the image near the spot you’d like to clean up. This gives the Healing Brush a point to sample from. Then, click on the point you’d like to clean up, and it should be ‘healed’ away. Bear in mind that the Healing Brush doesn’t work well near edges or areas of sharp contrast, as it will bring too much of the contrasting color into the sampled area.
4) The Brush Tool. Painting or drawing with brushes doesn’t usually help too much with compositing, but for now, be aware that it’s there. Same goes for the Eraser tool. These do have applications in advanced compositing, but we will discuss that later if needed.
5) The Clone Stamp tool- this looks like a rubber stamp. The Clone Stamp tool works a lot like the Healing Brush, but think of it as an actual rubber stamp. Rather than blurring together pixels from the sample area with pixels from the healed area, the Clone Stamp just copies the area you select onto a new part of the picture. Option-Click on the sample area, then click with the Clone Stamp to replicate part of the image in a new place.
6) The Zoom Tool. This one is key. It looks like a magnifying glass. Whenever you do something by hand in compositing, zoom in to 100% to check that it looks OK. The Zoom Tool defaults to zooming in (it shows up with a plus sign in the magnifying glass): hold down Option, and it will toggle to a minus to zoom out. Just click on the area of the image you’d like to zoom in on.
Selecting and Copying Images
Now we’ll take a look at a few tricks for selecting and copying images. Generally, think of this as copying and pasting text, but just with images. The one thing to bear in mind is that images have to be of the same resolution if you want to copy and paste them together and have them end up the same size. You can certainly copy and paste a 300dpi image into a 72 dpi image, but it will end up enormous in the 72dpi image- so it’s easiest to start out with images at the same resolution. If you do end up with a scale problem, check resolution first- it’s a common cause.
To select an image, start with the Lasso tool or the Polygonal Lasso tool. Draw entirely around the object you want to copy. This should bring up a blinking marquee around the object. You could just go to Edit: Copy and then Edit: Paste the image into your background, but let’s try to make it look at bit better.
Go up to the Select menu, and then Modify Selection. This brings up a wide range of options- generally, you want to slightly feather your edges to help blend the image into your background, and there are numerous other controls you can play with to refine your edges.
Finally, if the scale of a pasted image is wrong, you can tweak it by going to Edit: Transform: Scale. This will let you perform some basic scaling on your image.
Also, note that Photoshop automatically creates a new layer whenever you paste into another image- this helps a lot as you’re building up a large composite image.
A Helpful Note:
Please, please, please, feel free to experiment with Photoshop. This is truly the best way to learn. I will be introducing you to the set of tools I usually use to composite images in Photoshop: but there are many other ways to do it. Always experiment and play with new features and menus: if you don’t like the result, just hit Command-Z. So, if you’re stuck, try poking around the menus or looking at different tools: come with questions, and I’ll help out.
For Next Week: Shoot and capture your digital images. Start playing around with compositing them, and bring how-to questions to class next week.
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