YUP! Autotrace is another option. I tried out the fish with these settings -
Channel - Luminance
Tolerance - .1
Minimum Area - 2
Threshold - 90
Corner Roundness - 1
When Autotrace is not set to create a new layer (when the
Apply to new layer option is not selected), the masks that Autotrace creates are applied to the layer itself. Further the masks are created, have their Mask Modes set to None.
You may find that extraneous masks are created during the Autotrace procedure. Creating outlines such as this exercise is, will result in the mask that you want to use to be the last mask in the list. Simply select the said mask and change it's Mask Mode to Add. You may safely delete the unwanted masks.
When you need to use multiple masks to create a desired effect, it is useful to start working either from inside out or from outside and work your way inwards. The former seems to be the technique employed by the Autotrace algorithm.
Apply Effect>Matte>Simple Choker with a value of about 3 to clean up the edges. You may also feather the mask to create a softer edge. The downside to Autotrace is that you can't save it as a preset although it remembers its previous settings.
HTH
RoRK
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