As mentioned above, the image has been created in several steps, here’s brief description and a screenshot of the steps
From the original – colorful or grayscale – image we have to separate the elements which we do not want halftoned – for me it’s the white areas (step 1) and black borders (step 2). You may do it any way you want – Wand/magic lasso/Color selection/etc. Then, to quicker generate the halftone (note on converting to halftones below) we desaturate the image (step 3) and finally generate the halftone (step 4) via Filter / Pixelate / Color Halftone (set all the angles to 0). Later, we simply overlay the border and whites over the halftone and here we are.
Overlaying white areas may seem useless, yet in case of bigger halftone dot size it allows smoothing out the raster-jagged edges of these areas. It is not so well seen on my image, but in the one presented by you, the effect I mentioned is clearly seen in the case of the contours of ear/eye/hair (etc.).
Note: Keep in mind, that there’s another way to create halftones which may be more useful for you:
Image / Mode / Grayscale
Image / Mode / Bitmap
The way I have described above is quicker, at least for the presentation purposes.
2
Answers
The image you reference isn’t the result of a single filter. Hairs and outlines have likely been put in after the halftoning as well as eyes and ears.
As mentioned above, the image has been created in several steps, here’s brief description and a screenshot of the steps
From the original – colorful or grayscale – image we have to separate the elements which we do not want halftoned – for me it’s the white areas (step 1) and black borders (step 2). You may do it any way you want – Wand/magic lasso/Color selection/etc. Then, to quicker generate the halftone (note on converting to halftones below) we desaturate the image (step 3) and finally generate the halftone (step 4) via Filter / Pixelate / Color Halftone (set all the angles to 0). Later, we simply overlay the border and whites over the halftone and here we are.
Overlaying white areas may seem useless, yet in case of bigger halftone dot size it allows smoothing out the raster-jagged edges of these areas. It is not so well seen on my image, but in the one presented by you, the effect I mentioned is clearly seen in the case of the contours of ear/eye/hair (etc.).
Note: Keep in mind, that there’s another way to create halftones which may be more useful for you:
The way I have described above is quicker, at least for the presentation purposes.