This tool commonly used by photographers and designers looks simple but actually it could be so complex you wouldn’t believe. Covered topics: Crop tool for resizing images, crop on duplicated image, the “rule of thirds” in mind, and canvas extension.

Before we start make sure you are experimenting on image duplicates not on originals!

1. Crop tool for preparing images to print at desired size:

Our goal is to make 1280x960px @72ppi image to be printed as 6x4in@300ppi.

Images can be upsized or downsized. In one word you can make them bigger or smaller. Note: You can easily prepare image to work while reading this part of tutorial. Any image 640x480px @72ppi can be resized to 1280x960 @72ppi. Just go Image – Image Size and in pixel dimensions section enter 1280 and be sure constrain properties is checked. Now, we want to see how the image will look when printed at this native size. We can check this in two ways: one is to select zoom tool (or to just press “Z” on keyboard). Then click the print size button in toolbar. The second way is to call print with preview dialog - File – Print with preview. With image size I mentioned above we will get same results on screen when we click the actual pixels button or print size button in zoom toolbar. This is because image is suffering from small resolution for print purposes. Most photo printers operate between 200 to 360 dpi (200dpi is minimum). You will get excellent results if your image resolution is somewhere between these two values. OK, we confirmed that we must have higher resolution for this image. One will go to Image size dialog box and decheck “resample image” and enter 300ppi in resolution field and finally hit OK. But our image print size is 17,78x13,33in and after making correction for image resolution we will end with image print size 4,27x3,2in. But we want to get standard print with 6x4in (landscape) or 4x6in(portrait).

We can upsize image in two ways. One is with Image Size dialog box and the other is crop tool method. Both ways will do resambling with one of interpolation algorithms specified. Generally there are two interpolation algorithms: adaptive and non-adaptive. Photoshop has built in non-adaptive interpolation algorithms (Bicubic, Bicubic sharper, smoother...). Downside is that they produce artifacts (aliasing, blur and halos). Adaptive algorithms are implemented in software such as Qimage, Genuine Fractals and others. They are designed to provide artifact free interpolation.

First method – Image size dialog

For the first method go Image - Image Size… and be sure resample is checked as well as constrain properties. Enter 6in for width and Photoshop will automatically fill the height field with 4,5in. For the resample interpolation choose Bicubic smoother from drop down menu. Finally hit OK. Here is one problem. What is going to be with half of inch that was populated by Photoshop when you order 6inx4in image to be printed at your printer? Printer will crop again or machine will cut. Wait a minute! I would like to know exactly what is going to be with my images. Additional cropping may ruin the image. This is the reason why I prefer crop method.

Second method - Crop tool:

Make sure you “F it” once (press “F” once) recently opened image. Zoom out, select crop tool and enter values for width, height as well for desired resolution in toolbar (6 in, 4 in @300ppi). Make sure you have unchecked “Perspective”. Now we have to set interpolation method. I personally prefer to turn off resample in Image Size dialog box. I am setting interpolation method in General Preferences (Cmd/Ctrl + K). Crop tool communicates with your interpolation settings simply because no resembling could be done without interpolation method being involved.
Drag crop tool from top left corner to bottom right. When you have good cropping position press checkmark button in the right portion of crop toolbar (“Commit current crop operation”). Now, look at Image Size dialog box. Our image is set as desired: 6inx4in@300ppi. During the cropping you will notice that some parts of the image must be discarded. It’s OK because we will apply “rule of thirds” while cropping. With crop tool method you can do two things at once. Resampling and applying the rule of thirds - we will talk about this latter.

One thing to remember: We done our upsizing using bicubic or bicubic smoother interpolation. We also know that these algorithms are non-adaptive
and we could expect artifacts. Most evident will be blur. The rule of thumb: never upsize image twice, and never sharpen image before resampling. Sharp it after interpolation. If you sharpen image before, interpolation artifacts will be more visible after interpolation. Final steps in image editing process are: cropping/resizing and sharpening.

2. Crop on duplicated image:

You already know that smart Photoshopers always work on image duplicates. To duplicate image in Photoshop go with Option/Alt pressed to Image – Duplicate image. Close original. Now, you are ready to crop. Your background layer is unlocked. You performed cropping with bad results. Then you go to Image - Reveal all and nothing happens. You can’t go back and you are forced to close document.
Here is solution. First unlock image layer. Create selection with crop tool and stop for a second. You will see title in the crop toolbar called “Cropped area”. By default Delete is checked. Change it to “Hide” and perform cropping with Enter. Now, you can go step back with Image – Reveal all.

3. Crop with “rule of thirds” in mind:

The main goal for this kind of cropping is to improve image composition by taking the rule of thirds in account. The Rule of Thirds stands for dividing the image in thirds, both vertically and horizontally and placing the main focus points close to the four points where these lines intersect.
Good cropping will make images more interesting. Boring images often have object placed directly in center. Sometimes you must perform these shots.
Your final goal for performing this kind of cropping is to make more room for the parts of the image on the side where the eyes/head/object are facing/looking. Simply, if your object is looking on his/her right side then you should discard parts from object’s left side to get more room on the object’s right side.

To perform such a cropping set your crop tool to desired width, height and resolution. Place crop tool over the image and ask yourself what object should receive more attention. Imagine two lines horizontally and two vertically creating 4 intersects. Place your main object in one of 4 intersects and then crop.

Examples:
Original image was: 2272x1704@180ppi. The image below was optimized for web.

Cropped image: ready for print 6x4in@300ppi.
The image below optimized for web. Pay attention on aspect ratio.

Image with good composition.

You will see slices on this image. Yes, you can use them to preview rule of thirds after cropping. Just pick slice select tool(under the slice tool) and just click anywhere on image. In toolbar click on Divide slices… and check “divide vertically and horizontally”. Enter value: 3; To clear slices go View – Clear slices.

4. Extending canvas size of document:

Zoom out your document. “F” it (press F once). I will cover two scenarios. First scenario is to extend canvas and to get desired background color.
For this, set background color to white for example (if you want canvas to be white). Do not unlock your background layer ! Drag crop tool from top left to bottom right corner of the image. Press Shift + Option and drag one of the corner handlers. Shift + Option key combination will help you proportionally move selection from each of four edges. Finally, press commit button in the right corner of crop toolbar or just press Enter.

In the second scenario you want transparent canvas. Unlock image layer and perform the same steps from above. Foreground/Background color are not important. Now you can add new layer below the image layer and apply color or some effect.

Real world example – business card. All you need is a cool image or background and some room for text. Here is how to do it in one single step> Open your image and set the crop tool to 3.75x2.25in (0.25in for bleeds included) and set the resolution to 300ppi. Choose your background color and keep locked or unlock image layer (see previous scenarios). Now, place crop rectangle over the image but move rectangle to left if you want text area to be on the left side of the card. Example provided below.
Note: When you create selection with crop tool you can rotate selection – this is for vertical business cards.

Now, you know how to create bunch of business cards from images and cool backgrounds in just a second. Text layer should be moved with move tool from one card to another.