How to Make Amazing Halftone Effects with Photoshop

If you look really closely at an image in a printed newspaper or magazine you’ll see that what appears at first to be “continuous tone” (like a photograph) is actually constructed of thousands of tiny spots. This is called a halftone. But if you make those spots bigger, you break the illusion and the spots (or dots or whatever you want to call them) become an integral part of the image itself.

Making Halftones

But how can you make these halftone effects yourself? It turns out to be super easy in Photoshop.

To make the four-color “rosette” halftone in the middle of the image above, I simply chose Filter > Pixelate > Color Halftone. On a color image, you get multiple halftones that overlap. But on a grayscale image, you get circular dots that grow larger and larger:

Halftones

Making Better Halftones

The Color Halftone filter does an okay job of making halftones, but there is another, far more powerful method. This is what I usually do:

First, here’s the image that I’m going to be working with:

spiral

I just made it by creating an “angle gradient” in Photoshop and then running the Twirl filter on it. I want a black-and-white halftone, so I’ll first convert the RGB image to Grayscale:

convert to gray

And then I’ll head back to the Image > Mode submenu and choose Bitmap. When I do this, Photoshop asks me what I want to do with gray tones in the image:

convert to bitmap in photoshop

If I choose Threshold from the Method pop-up menu, then Photoshop simply makes all my dark gray pixels black and light gray pixels white. That’s not very interesting. Instead, I choose Halftone Screen from the Use pop-up menu and click OK. This is where the real control lies:

convert to halftone screen

You can choose a Frequency, an Angle, and a Shape for the halftone. In the image at the beginning of this article, I used the Round shape, which makes circles.

Halftone6

But if you look really closely, these are different than the circles that the filter uses. Instead of circles that just get bigger and bigger, they’re circles that actually invert in the darker tones:

real round halftone spots

This is a more traditional halftone spot shape, reflecting how halftones really look in print.

But you don’t have to use the Round spot here. You can use Line:

line screen

or Cross:

cross hafltone

…or several other screens. Notice that I’m adjusting the frequency (lower frequency numbers make larger “spots”) and angle of the grid in each of these examples.

Adjusting Image Resolution

I skipped over one important setting earlier on: the Output field in the Bitmap dialog box. This lets you control the resolution of the image after you apply the halftone effect. If you are planning on printing your image, you’re probably going to want to set this to 1000 or more (for super smooth edges on your halftones, I would recommend 1500 or 2000 ppi).

If you’re just making Web graphics, then you’ll want to set this to something smaller. While you may be tempted to use 72 or 96 ppi here for Web graphics, I would, instead, recommend that you use perhaps 300 or so. Then after you make the halftone, use the Image > Mode menu to set it back to Grayscale, then change it back to RGB, and then change the resolution of the image to 72 or 96 ppi using Image > Image Size (by resampling it). This will result in a softer, more elegant effect. Again, that’s just for on-screen images. This also lets you export as PNG or JPEG.

How to Save your Image for Print

If you are printing your high-resolution bitmapped image, you’ll leave it set to Bitmap mode in Photoshop (that just means every pixel is either black or white). Then you can save it as a PSD or TIFF file.

The nice thing about bitmapped images like this is that you can place them in InDesign and then colorize them. (First select the image inside the frame, and then choose a color from the Swatches or Color panel.)

Halftone8

The halftone effect lets you create a vast number of variations from your images. Experiment! Play! Make multiple versions and overprint one over the other.

block prints

Enjoy!

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Posted on: June 10, 2015

David Blatner

David Blatner is the author or co-author of 15 books, including Real World InDesign, Spectrums: Our Mind-Boggling Universe From Infinitesimal to Infinity, and The Joy of Pi. He is also the author of InDesign Essential Training and the InDesign Insider Training titles at lynda.com. David is the co-host of InDesignSecrets and PePcon: The Print + ePublishing Conference, and is the co-founder of Creative Publishing Network.

25 Comments on How to Make Amazing Halftone Effects with Photoshop

  1. Awesome article! I definitely want to try this out! Besides setting to at least 1000, do you have any other recommendations for those planning to print something like this?

    • David Blatner

      June 15, 2015 at 4:07 pm

      I can’t think of anything else. If you’re printing on a high-resolution device (platesetter), you may want 1500+ ppi. And you probably want to make it “at size” (so that you don’t have to resize it later).

  2. Very nice, thanks! I’ll definitely put this to use.

  3. Very Interesting, Thank you.

  4. Yes… its me again!

    That was a great tutorial, and it really is a great way to punch up photos.

    Its especially helpful having almost a two in one tool, to not only up the colours but also add some impact with tasteful contrast.

    Keep the tutorials coming! I continue to use previous tutorial techniques in my processing all the time!

    Thanks!

  5. That’s a perfect explanation for creating the poster effect I am after. Thanks!

  6. I’ve never heard of going to such high resolutions for print. 1,000-2000 ppi? What happened to the 300 standard?

    • You very rarely need higher than 250 or 300 ppi for grayscale or color images. But for bitmap (black-and-white-pixels-only) you need much higher resolution. Of course, if you’re only printing to a laser printer or inkjet you don’t need 2000 ppi, but if you’re printing to a platesetter or high end digital printer, you need it, or else you’ll see jaggy edges.

  7. For more advanced halftone techniques you might want to use specialized software, like HalftonePro. It also allows saving as a vector to save you the pain of tracing a raster halftone.

  8. David, this is so useful, and an area of Photoshop I’ve never played with. But can you please describe how you created the ‘angle gradient’ you started with before applying the twirl filter? When I try to duplicate your steps, I can’t get that strong line between the light and dark’ my twirl is feathered & fuzzy.

  9. Using your instructions, the half tone does take on the “inverted”, but the dots all remain the same size. What can I do to make the dots variable sizes?

  10. Also, is there a way to influence the minimum and maximum size of the dots?

    • David Blatner

      July 22, 2016 at 6:05 pm

      The dot size is based on the gray value. 5% gray will be a small dot, and 50% gray should be larger one.

  11. Thank You, this really helped!

  12. Fantastic tutorial. Is there a way to experiment with the bitmap options, so I can play around with the different method, frequency, angle and so on to see what results. For eg. usually there’s a preview mode you can tick and you can see the results immediately, this doesn’t appear here. What I’ve been doing is a bit tiresome, and that’s basically undoing back to greyscale, then doing the whole mode-bitmap-options step again.

    Many thanks in advance

  13. The nice thing about bitmapped images like this is that you can place them in InDesign and then colorize them. (First select the image inside the frame, and then choose a color from the Swatches or Color panel.)

  14. David, thank you very much for the tutorial. I have an image which I wish to represent in half tone for a silkscreen process. it is mainly black and white but there is a small amount of green and pink in it too. I figure that I should be able to represent it if I have white paper and then three colours black green and pink. How could I do this in photoshop? regards Sam

  15. thanks… i keep getting an error message: could not complete the command because of a program error
    Any idea what i might be doing wrong?

    • Kim: That’s weird. A “program error” is usually something serious (like crashing). I would try quitting and restarting the program. Not sure what could cause that.

  16. how would i add halftones on a portrait with colour? like i have a digital portrait of a celebrity and i’m trying to add a halftone but it removes the colour and makes it in grayscale which is not the way i want it? HELP

  17. My Friend, Mercedes Benz once created a printed advertisement in which by looking closely at the reticulation grid with a magnifying glass it was possible to distinguish the MB logo in every single dot. How did they do it?!

  18. Nice read. Its commonly unexplored, whats possible with psd. We used this to make aluminum and copperplate prints.

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