How to create a dotted mosaic effect in Photoshop
Tips & Tutorials, by Mark White
April 24, 2013
A free tutorial for creating a dotted image effect – for this technique to work well, you’ll need a bright, high-contrast image
Start by going to Filter>Pixelate>Mosaic. Choose a suitable Cell Size, depending on how bold you want the spots, and make a note of the cell size.
Create a new document, choosing the same Height and Width in pixels as the Cell Size you chose within the Mosaic filter.
On this new document, fill with black and double-click the Background Layer to promote it to a layer. Use the Elliptical Marquee Tool to make a circular selection within the black document.
Hit the Backspace key to delete the area within the selection, and go to Select>Deselect. Now go to Edit>Define Pattern, giving the pattern a name.
Return to the main document, double-click the Background Layer and add a layer mask via Layer>Layer Mask>Reveal All.
Click directly on the layer mask and go to Edit>Fill choosing Pattern for Contents. Choose your pattern from the Pattern swatch. Finish by adding a Solid Color layer, choosing a colour to drop behind this layer at the bottom of the stack.