Looking for a process similar to posterize

[Lois KP]

Hello! maybe 6? years ago in art class we used something in photoshop, visually similar to posterize, to reduce an image to a certain amount of colours to use in screen printing, we'd then separate the colours to different layers and use them to print with. I'm looking to find the tool that was used for this - The only example I have are photos of a printed out image using this process. I remember it coming up with a small grey pop up in the middle of the screen, and you were able to alter a slider to change the number, which would result in a more/less detailed image. Have been wondering this for years - would appreciate the help so much! Thank you 🙂 

[Myra Ferguson]

The images aren't opening up for me, but I'm wondering if they were using Duotone options. The approach would be the following:

1. Open your image
2. Save a copy (File > Save a Copy...) because this process will flattened your image
3. Go to Image > Mode > Grayscale (if your image isn't flattened, this will flatten it. Also, if you prefer to control the conversion to grayscale, apply the Black and White adjustment layer first)
4. Go to Image > Mode > Duotone
5. In the Duotone Options, you can set the Type to Monotone, Duotone, Tritone, and Quadtone. These options correspond to the number of inks that you can use. 
6. Set a color for each ink.

[Chuck Uebele]

Does the posterize filter not work for you? This is still available under the image>adjustments menu.

[Lois KP · Accepted solution]

Nevermind I found it! You have to convert the image to a smart object, and then go to filter > filter gallery > artistic cutout - looks much more appealing than posterize to me. 

Thanks for the helpful responses!