How to use Grab utility on macOS and Mac OS X?

How to launch and use Grab utility on macOS and Mac OS X?

Many Mac users are already familiar with the Utility folder and the useful tools it contains such as Terminal, Activity Monitor, Disk Utility, Console, Keychain Access, etc. Some of these apps are helpful when seeking solutions to problems you may have encountered.

Among these useful apps is Grab, which is based on capturing a computer screen image. The Mac OS has built-in functions for screen capturing, they are reached through keyboard combinations such as Command, Shift and 3 or 4, however, the Grab app is much more powerful, and includes different image formats, a timer screenshot function, and more. In this article, we will cover all types of screenshots, troubleshooting, and how to set up the Grab app to deliver good quality images.

grab-introduction

Table of Contents:

Capabilities of Grab

As mentioned, the Grab app has higher functionality than Mac's built-in screenshot function - here is a clear view of its potential:

  • Is able to capture just a portion of the screen.
  • Takes an image grab of a selected window.
  • Performs a Timed Screenshot. This function allows you to take a screen grab after 10 seconds.
  • Allows you to select a type of pointer (cursor) and also to show or hide it in screenshots. To set pointer settings, open Grab Preferences and select the type of pointer, or disable it.
  • Takes a picture of the entire screen, including multiple-monitor screens.
  • Saves pictures in various image formats such as JPEG, PNG, and TIFF.
  • Owns a small 'tooltip' displaying the exact coordinate of your pointer, which transforms into the amount of pixels selected when selecting an area.

grab-about

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Use of the Grab utility

This app has a simple interface, however, some steps might be confusing. Here, we walk step-by-step though all Grab functions. There are several ways to launch the app. As mentioned above, the app is within the Utilities folder, so we can use Spotlight, launchpad, or finder to start Grab. In finder, go to Applications, choose Utilities, and select Grab. In launchpad, Grab is within Other.

spotlight-grab

Take a screenshot of selected area in your screen

When the app is launched, click on Capture on Grab's menu at top of your screen, and then choose Selection or simply press Shift, Command and A together on your keyboard. You will notice Grab's information message. Now select your desired area by dragging with your mouse. When you have finished selecting, the picture will appear in a new window where you can save the image in a specified destination folder with a filename you provide.

select-grab-draggin

Take a picture of desired window

Select Capture from Grab's menu, and then choose Window or simply press the keyboard shortcut Shift, Command and W. In the popped-up window, click Choose Window. Left click to select the window required to capture, and then save it.

window-grab

Capture your entire screen

Select Capture from Grab's menu, choose Screen or simply press the keyboard combination of Command and Z to start capturing the whole screen. An information message will pop-up stating that the image will be taken when you left-click the screen anywhere (outside the message).

screen-grab

Perform a timed screenshot

To launch a timed screenshot function, go to Capture in Grab's menu and choose Timed Screen or use the keyboard shortcut Shift, Command and Z. The activation window will pop up and leave 10 seconds before capturing from the moment you clicked Start Timer. This function will take a picture of the entire screen - it is very useful when you need to take a screenshot of menus or menu options.

timed-screenshot-grab

Check the details of taken screenshot

To look up information about the screen capture, click Window and choose Inspector, or simply press Command and 1 together. This information is available before image is saved, so you can check the dimensions and file size with the TIFF format, which is default Grab format for screen captures. You can change this format when you are not saving the screenshot.

inspect-image-grab

Image quality

It is often useful to change the resolution of image. The Grab app usually captures images at high-resolution, however, this is restricted to your display resolution. To achieve a better quality of screenshot, ensure your display is at highest available resolution. To change your device display resolution, open the Mac's System Preferences and choose Displays. Check that the display is set to highest number of pixels available.

display-resolution

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Change default screenshot format

The default format when saving captures is generally PNG and can be changed easily using terminal and a few simple commands. Mac supports PNG, JPG, TIFF, GIF, and PDF formats, so you can choose any of these. Launch terminal, which is under the Utilities folder or use spotlight.

  • To set JPEG format as the default, type the terminal command: defaults write com.apple.screencapture type jpg
  • To set TIFF, type: defaults write com.apple.screencapture type tiff
  • To set GIF, type: defaults write com.apple.screencapture type gif
  • Set PDF, type: defaults write com.apple.screencapture type pdf
  • If you wish to return the format to PNG, type: defaults write com.apple.screencapture type png  

The changes will not take effect until you restart the Mac. Alternatively, you can use the additional terminal command: killall SystemUIServer. The Mac will then be forced to reboot and the system will use the new settings.

terminal-change-format

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Grab utility stopped working after macOS update

Occassionally, the app might fail to work after a system update. This issue can be due to a corrupted Grab preference file. To see if this is the case on your system, open Finder, choose Go from the Finder's menu at top of your screen, select Go to Folder, and type the following path: ~/Library/Preferences/com.apple.grab.plist and press return. Move the selected file to Trash or your Desktop and restart the Mac. Once the computer has completely rebooted, attempt to launch Grab again. If this step helped, delete the old preference file. Otherwise, try reinstalling the Grab app using macOS Recovery. Finally, if none of these solutions fixes the problem, you could reinstall macOS.

preference-file-grab

Detailed steps on how to reinstall macOS.

An alternative method to take a screenshot on the Mac is to use built-in screenshot function.

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Video Showing how to use Grab utility on macOS and Mac OS X

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