Random Thoughts – Randocity!

How to setup a black / blank screensaver on a Mac or Windows computer

Posted in Apple, Mac OS X by commorancy on February 18, 2017

Updated for 2018. This technique should work on any desktop operating system and this technique is quite easy to set up. I also realize that Windows offers a Blank screen saver that kind of negates this technique, but here it is anyway. And yes, it does work on Notebooks, too. Let’s explore.

Mac Computers

I’m starting with the Mac because it seems so much less obvious considering how ‘easy’ it should be for a Mac. One of the things you’ll notice in the screensaver area is that there is no blank or black screen saver. What people have suggested instead of a black screensaver is to enable the energy saver. While this works to turn off the backlight and save it, power savings does other unfortunate things to a MacOS computer at the same time.

Energy Saver Problems

“What problems”, you ask? Well, Apple has taken it upon themselves to also shut down a number of other critical components when the power saver is activated. Windows may be doing this as well. Yes, it does turn off the backlight. Unfortunately, with that it also turns the WiFi and networking off.  This means that if you have a VPN running, your VPN will disconnect. If your company invests in VPN software which does not self-connect on WiFi reactivation, you’re stuck reentering your passwords and setting up your terminals all over again. Unfortunately, I have no control over the software that’s used by my company and I have to live with it. So, I avoid the energy saver system like the plague to avoid random VPN disconnection. I use a screen saver instead. No, it doesn’t turn off the backlight, but that’s a small problem.

A Screen Saver?

A little history, a screen saver was used primarily to prevent burn-in on CRT tubes. It’s also distinctly different from power saver mode. Since the days of CRT tubes have long since passed, we are now using LCD screens with LED back or side lights. Some screens are made of OLED technology, which means that each pixel is a self-illuminated RGB LED light. With either of the LCD or OLED technologies, the chance for burn-in is almost non-existent. However, some LCD screens can show latent imagery under certain specific conditions if left sitting with the same static image for too long. So, a screen saver is still useful. However, a screen saver is most useful as a screen lock indicator.

Black Screen Saver on Mac

The problem is, the Mac doesn’t offer a black screensaver. It expects you to use images to cycle or other screen savers like a bouncing clock or a bouncing apple or similar.

However, I just want a simple black screen with no movement at all. You’re not going to burn-in your screen with a simple black surface, even though LCDs don’t really do that. To wit, you’ll notice no settings for that ..

screensaver-l

There is no screen saver above that provides a blank or black only screen. So, how do you do it?

Here are the steps:

  1. Find your current Mac’s screen resolution in Finder using applelogoascii => About This Mac. Then click on Display and look for your resolution. In the below example, you see 1440 x 900. It’ll be whatever your Mac offers.display
  2. Make note of the resolution above and jump to Creating a blank image using The Gimp section.

Blank Screensaver on other operating systems

If you find that your Windows system doesn’t offer a blank screen saver, you can follow these instructions:

Windows 7

  1. Windows Button => Control Panel => Display
  2. In Display, click Adjust Resolution
  3. Make note of screen resolution

Windows 10

  1. Windows Button => Control Panel => Appearance and Personalization => Display
  2. In Display, click Change display settings
  3. When the Settings window opens, make sure it’s still on Display. Then, scroll to the bottom of the right side panel and click Advanced display settings
  4. Make note of the screen resolution

Linux

  • Refer to your Preferences and Display settings to find the current screen resolution

Create a blank image using The Gimp

From here, what you’re going to do next is create a blank image in the resolution of your screen. It’s best to cover the entire screen’s pixels with black rather than, say some lower res image like 1024 x 768. This is the reason for discovering the resolution above. Using the full screen resolution prevents unexpected issues with the screen saver’s stretching (or not stretching) the pixels properly. This process can be used on all operating systems that have The Gimp installed.

To create a blank image in The Gimp, use the following:

  1. Open the Gimp (download it here — it’s free)
  2. Make sure your foreground and background colors look like so, with black on left top and white on right bottom:gimpcolors
  3. In the Gimp, File => New…
  4. Then, type in the resolution you found from from your operating system into the Width and Height fields (making sure to put the correct values in each field).
  5. Click Advanced Options and change Fill with: to Foreground Color
  6. Click, OK
  7. You should now see an image filled with black.
  8. Save the image using File => Export As… and type in a filename and change the file type from .png to .jpg to make the image smaller. Be sure to remember the folder where you are about to save your file.
  9. In the Export image as JPEG window, click the Export button
  10. You now have a new black image in the resolution of your screen.
  11. From the GIMP menu => Quit GIMP

Now that you have a saved black image, you need to add it to a list of images where your screen saver looks.

Adding this image to the Mac screen saver

This is a fairly simple concept. You will now use this newly created black image as your only screen saver image. So, no matter what the cycle rate is, it will always cycle back to this same blank image all of the time.

Here’s what I did on the Mac. I created a folder called black-image under my Pictures directory. I’ve placed my newly created image into /Users/myuser/Pictures/black-image/black-image.jpg. I’ve put it in a separate folder because that’s how Mac finds images… by folder. Now, select the folder under the ‘Classic’ screen saver using settings like so:

choosefolder

Where the arrow points, click that selection area, it will open a file requester and then choose the folder where your new black-image.jpg file is. Once you set it here, your screen will turn black when the screen saver activates (as in my case, in 30 minutes).

Windows or Linux

While I know that Windows has a Blank screen saver built-in, you can also use this technique by choosing the screen saver as Photos, then choose the folder where your blank-image is located. For Linux, simply perform the same setup using your preferences to select the photo folder where your save black-image.jpg exists. Once you do this, the screen saver will only show that single black image once the screen saver has activated.

This is actually the safest technique rather than relying on plugins or programs to provide a black screen. It will also continue to work should Microsoft decide, in their infinite wisdom, to be like Mac and remove the Blank screen saver in the next version of Windows.

I prefer this technique to using the power saver because of the issues mentioned above. This allows me to set up a black screen with the backlight still on which also keeps my VPN active. Of course, if you don’t deal with VPNs, then by all means use the power saver.

ScreenSaver Selection

Note that Mac and Windows (and probably Linux) offer a various number of image transition effects. You’ll want to be sure to choose the simplest effect choice for your black image. On the Mac, the fade-to-black or fade-between-images effect choices include the ‘Classic’ or ‘Ken Burns’ effects. These offer simple fades between each image.

You won’t want to choose an effect that adds white (or any other color borders) around the black image. Choose a screensaver effect that offers a simple fade and no borders. Otherwise, it will defeat the purpose of setting this up.

The screensaver effects offer previews of how the images will transition when the screensaver is running. Be sure to watch the preview of the screensaver plugin to ensure it will provide you with a solid black screen. You may have to use a few real images in the screensaver to find the effect that offers a simple fade transition.

[UPDATE: 9/13/2019]

Screen Aura

A recent reader pointed out that the black image seemed to still have an aura of illumination and wasn’t 100% inky black. As I’ve stated above, the backlight remains on when using the above black image screensaver technique. This means that the backlight light will show through the image and may make your black screen appear faintly dark gray. It may also be more pronounced if your backlight is at 100% brightness or when you’re sitting to the side of your display as LCD displays don’t always offer full 180º viewing angles. At very sharp angles to the screen, the backlight illumination may appear brighter.

The only way to really fix this is to reduce the brightness of your backlight. Most external monitors allow for this. Notebook attached screens usually have a brightness setting built into the keyboard. You can then reduce the brightness of the backlight by pressing the screen brightness down button on a notebook keyboard.

If you have an external monitor attached to your computer, turning down the backlight brightness involves using the external monitor’s menu system. The only way to turn off the backlight on an external monitor is to put the computer into a power saving mode… not in any way the same as using a black screensaver.

OLED Monitors and Contrast Ratio

If you truly want inky blackness when using a black screensaver image, you’ll need to invest in an OLED monitor. This technology uses very small LEDs for each pixel. When you use a black image as a screensaver, each pixel image will turn off each individual LED on the OLED panel making the screen 100% as black as it can get… or, in other words, it will look like the screen is turned off. Replacing a backlit LCD monitor with an OLED monitor is the only way to get true inky blackness using a black image screensaver. Otherwise, you have to manually turn down the backlight brightness.

Looking at contrast ratios is important when buying any display. The higher the contrast ratio, the deeper the blacks will be. OLED screens have some of the highest contrast ratios of any displays on the market, for obvious reasons.

OLED Monitor Scams

Be careful when shopping for OLED monitors. Searching on Amazon for ‘OLED Monitor’ actually brought up many listings for LCD backlit monitors. Even clicking the ‘OLED Monitor’ filter checkbox on the left side of Amazon’s listings still brought up many incorrectly labeled LCD backlit monitors. Don’t be tricked into buying an LCD backlit monitor thinking you’ve bought an OLED monitor.

Make sure that you’ve read the technical specifications of that model monitor carefully. You may need to visit the manufacturer’s web site to find this technical information for that model number. The manufacturer will list the panel type included in its display. However, Amazon’s listing may be entirely wrong. This same caveat can be had if you visit Best Buy or a local retailer. Additionally, I can almost guarantee none of the monitors sold at Target or Walmart will have this technology. OLED technology is much more expensive to produce than LCD backlit displays. For this reason, discount retailers aren’t likely to carry many (or any) OLED monitors… and if they do, they’ll usually cost twice the price of an LCD backlit monitor.

Variable Backlight Contrast (aka The Poor Man’s OLED)

Some LCD backlit monitors contain variable backlight contrast. These are usually in the form of TV monitors versus computer monitors. While this technology does not provide as nearly an inky black blackness as an OLED monitor, it can come very close. Hence, it being known as the poor man’s OLED.  This technology offers backlights that automatically vary their brightness based on the image currently being shown. This means that when a black image is shown, the backlights are almost 100% off. This technology hasn’t made it into many, if any, computer monitors, but it is in HDMI based TV monitors. If you can find a TV that contains this variable backlight contrast, it can perform a similar inky black function as an OLED monitor, but costing less money to purchase. However, again, you’ll need to read the tech specs of the monitor to determine if it contains this variable contrast backlight system. Many monitors don’t offer this variable system and instead offer only static brightness that must be manually adjusted.

What about QLED?

QLED is another backlit LCD technology and follows all of the same rules as LCD backlit screens. If the QLED monitor ships with variable backlight contrast, then it may be a good candidate for inky blacks. If it doesn’t have variable contrast backlights, then it won’t provide this.

As an FYI, I personally bought my 4K Vizio monitor because it had variable contrast backlight technology. When portions of the screen go black, these sections of the screens have their backlights nearly turn off. It’s a smart design technology used to mimic the contrast levels you can find in a more expensive OLED panels. So, now you know.

If this tutorial was helpful to you, please leave a comment below and let me know.

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12 Responses

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  1. Rob said, on September 27, 2019 at 2:15 pm

    What a great workaround this is! Thank you! I’m using a MacMini as a music server with HDMI to my receiver. There was no way for me to turn off the TV without disengaging the server due to HDMI handshaking which I have no control over. Your solution was the answer. Thanks again.

    Liked by 1 person

  2. Ron said, on September 11, 2019 at 9:32 pm

    Good write up. However, my black image isn’t totally black. It has sort of a backlit aura to it.

    Like

    • commorancy said, on September 12, 2019 at 9:51 am

      Hi Ron,

      Yes, that’s normal. A screen saver doesn’t disable the backlight. This means that the backlight will still filter through the black image. This will then leave the screen as a black with a glow. The glow is from the backlight.

      The only way to get the backlight to turn off is using the power saver. This will disable the backlight on a notebook. However, if you’re using this on a desktop with a separate monitor, there may not be a way to disable the backlight. Disabling the backlight is the only way to completely make the screen totally black.

      I forgot to mention that enabling a power saver on a mac cuts off network interfaces when it activates. This means connectivity loss to network drives and will disconnect any VPNs you may have active. This can be a hassle if you are relying on network drives to store your music or other entertainment or if you are in a work environment and need your VPN to remain active throughout your work day.

      One other way to get a totally black screen with screen saver is to buy and use an OLED screen. These screens don’t operate with a backlight and instead, when the pixels are black, the OLEDs are entirely turned off creating a solid black screen using only a screen saver. The other way to reduce the aura is to manually reduce the backlight brightness. Most screens turn the backlight up too much by default. Turning the backlight brightness down can reduce glare to your eyes and will reduce the aura you’re seeing behind the black image.

      Hopefully this helps.

      Like

      • Ron said, on September 15, 2019 at 5:11 am

        Thank you very much for the response. Also, in the interest of accuracy, should instruction #5 be re-worded (Click Advanced Options and change Fill with: to Background Color) to say Foreground Color given that the black square is on top?

        Like

        • commorancy said, on September 16, 2019 at 6:48 am

          Corrected. Thanks for catching this. I believe I ended up uploading the wrong image when I released the article and never caught that. Though, I think most readers have figured this one out.

          Like

  3. Bob D. said, on May 17, 2019 at 7:59 am

    Looks like Mohave no longer includes the “Source” option in the Screen Saver window under Preferences. Any work around?

    Like

    • commorancy said, on May 22, 2019 at 1:30 pm

      Hi Bob,

      In Mojave, the screensaver is named ‘Classic’. Choose ‘Source:’ under this screensaver and then choose the folder where the image exists.

      Like

  4. John Forward (@forwardesign) said, on October 23, 2018 at 9:29 am

    I tried this but got an animation of a black picture in a white frame popping around the screen, so I knew that would keep me awake, so I removed the black JPEG and now it shows a tiny bit of text (No photos.) and a small digital clock – which is what I really wanted in the first place, so bravo me.

    Like

    • commorancy said, on October 26, 2018 at 3:25 pm

      Hi John, thanks for your comment. You’ll have to be sure not to select any specialty screensaver viewers. Some specialty viewers perform tricks with the images, like bouncing them around the screen. You want the simplest viewer you can find that simply shows images full screen with a black fade between each image. This one should still be there on your system. You might have to select some real images to locate this screensaver viewer. Once you locate it, choose the black image and it should be fine.

      Like

    • commorancy said, on October 26, 2018 at 3:28 pm

      I will update the article to reflect this issue. Thanks for pointing this out.

      Like

  5. Noel Body said, on October 9, 2018 at 6:00 am

    Another way to do this is point to a folder with no images in it (High Sierra).

    Liked by 1 person


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