Creating a dotted line in Photoshop is quite hard, but it can be done, and it is really easy to do. All you will need is Photoshop and 5 minutes. You can click any of the images to see the full size.
Step 1) Open up the brushes and select the advance options pallet.
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Step 2) Select brush tip shape and select a small brush. 5 pixels is a good size.
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Step 3) Untick everything, smoothing is usually the only one enabled.
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Step 4) But spacing up, the more you space it the bigger the distance between the dots.
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Step 5) Apply to what you want, you now have a dotted line. You can resize it and blur it just like a normal brush.
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