Process Digital Reference Photos in Photoshop

Knowing how to process digital reference photos is as important to today’s artist as knowing the best art materials. Most of us need at least a basic knowledge to make the best use of our photographs.

Welcome back to my month-long series on using photographs to create art. In the first post, I shared a link to an article on composing images so colors pop. Last week we talked about three things to remember when composing through the lens.

A basic explanation is all we have time for today, but there are lots of video tutorials for those who want more in-depth information. The methods I’m about to share are what I’ve been using since before The Cloud. Outdated, perhaps, but still useful!

Today, we’ll look at preparing digital photographs using Photoshop. I use Photoshop 7.0 on a Mac, so there may be some differences in procedure, depending on the version of Photoshop you use.

How to Process Digital Reference Photos in Photoshop

Step 1

Import photos into Photoshop. Since you may be bringing photos in from a variety of sources, I won’t go into detail on this part of the process beyond saying that you can open photos from most devices through Photoshop by clicking on the FILE drop down menu and selecting OPEN. That opens a dialogue box that allows you to select any device or drive connected to the computer.

Choose the photo you want to work with.

Save it with a new name into a new folder before making changes. It’s always prudent to save the original file. That way, if you make mistakes, you can go back to the original and start over. All you will have lost is time.

Step 2

Few photos are perfect. At minimum, most will need a bit of tweaking to be optimal. If you’re planning representational artwork, a few things to consider are:

• Composition
• Color Quality
• Lighting
• Sharpness

If the artwork you have in mind is less representational, you can also play with filters, color, and screens or many of the graphic tools available on Photoshop. But that’s a post for another time.

The first thing I do is fit the photo to the shape of the painting or drawing I want to do. At the very least, I crop out excess area. The photo I’m using for this demonstration has more foreground than I want in a painting.

So I crop the image by selecting the area I want to use (see dotted line below). Select the drop down menu, IMAGE, and click on CROP.

Save the new image.

Step 3

You can also change the size of the image. For the purpose of this demonstration, I changed the width of the image to 24 inches, then cropped it so the vertical size was 18 inches. The resulting image is 18×24 inches, a standard canvas size.

To change the size of an photograph, click on the IMAGE drop down menu and click on IMAGE SIZE. The following dialogue box will appear.

Under “Document Size” type in the numbers you want. The box to the right is for setting the measurement standard. In this case, inches. You can also choose picas, centimeters, and columns, in addition to other options. Choose the measuring standard you prefer and click OK.

You can also change the resolution if you wish. The default is 72, which is shown above. The larger the number, the better the resolution and the larger the overall file.

The numbers at the top of the dialogue box (Pixel Dimensions) will automatically change with each change you make in Document Size. You can also affect the numbers in the Document Size section by changing the numbers in the Pixel Dimensions. Since most standard sizes of paper and canvas are not measured in pixels, I generally don’t do anything with Pixel Dimensions.

The checked boxes Constrain Proportions and Resample Image are default settings. Uncheck Constrain Proportions if you want to change only one side. This will cause the image to distort.

NOTE: Changing the size and cropping the image are interchangeable steps. In some cases, it may be better to crop first, then change the size. In other cases, changing the size first might be better.

Step 4

I next changed the contrast and brightness of the image by using Photoshop’s standard filters. Click IMAGE, then choose ADJUSTMENTS and AUTO LEVELS.

You can see below how Photoshop adjusted my photograph. The top image is the original color, brightness and contrast settings.

The lower image shows the corrections.

If you like the changes, save the new image.

Step 5

If you don’t like the changes Photoshop made in Step 4, undo (Control+Z). You can then make individual changes to suit your preferences.

BRIGHTNESS/CONTRAST
To change the brightness or contrast, click on the IMAGE drop down menu and select BRIGHTNESS/CONTRAST.

A dialogue box with two slider controls will appear. The top one is for brightness. Sliding the control to the right increases brightness. Sliding it to the left decreases brightness.

The lower control is for contrast. Again, sliding it to the right increases contrast and sliding it to the left decreases contrasts.

You can change either brightness or contrast or you can change both. You can also increase one and decrease the other, so you have virtually unlimited choices in changing these two filters through this dialogue box.

The value of brightness and contrast is most evident when you want to manipulate poorly lighted photographs. Photographs of gray days can be brightened by increasing the brightness levels and contrast levels in Photoshop.

The left half of the image below shows normal settings. The right half shows increases in both brightness and contrast. Note that some details are more clear with the changes, while other details disappear.

You can’t make a gray day sunny, but you can create the illusion of brighter light, which will aid your painting if you want to paint a particular scene in bright light, but the only photographs you have are of gray days.

Step 6

To adjust COLOR, select IMAGE > ADJUSTMENTS > COLOR BALANCE.

A dialogue box will open with a row of three boxes labeled Color Levels at the top and three slider controls below. The slider controls correspond to each of the three non-black printing colors: Cyan, Magenta, and Yellow.

The boxes in the top row correspond to the slider controls.

In this illustration, I changed the Cyan setting by sliding the control bar to the right. The number in the first box at the top shows the amount of change and indicates that I’ve increased the blue by plus 10.

At the bottom of the box is the tone balance. This allows you to change specific areas in the photograph. By clicking on Shadows, you can change the color of the shadows without changing mid-tones or highlights. The default setting is mid-tones, which means the change I made in the paragraph above affects the mid-tones, but not the shadows or highlights.

Preserve Luminosity is also a default setting.

By clicking the Preview box at the right, your changes will appear in the photograph, so you can see what they look like before committing to them. This is always a good idea.

But even if you do commit to the changes, then decide you don’t like them, you can still undo them by typing Control+Z BEFORE saving the image.

It’s advisable to experiment with color settings. How much color change you need depends on the type of artwork you want to do. For portrait work, for example, I make color changes only to correct distortions. I usually make those changes only if I took the images myself and know the color is not accurate.

That’s How I Process Digital Reference Photos

As I mentioned, this demo features Photoshop on a G4 Macintosh, but you can do the same things in any photo editor on any platform. These days, you can probably do most of them on your phone!

For example, when I work on our PC, I use GIMP or Irfanview to process digital reference photos. Irfanview is great for simple adjustments, while GIMP works a lot like Photoshop for more complex work. Both are free installations.

Most of the time, these changes are the only changes necessary. Your photo will now be ready for the next step in your working process, whether it’s printing a copy to work from, creating computer generated compositions, or putting a drawing grid over the photograph.