when i follow the tutorial making a sword, when i make a mask it always started with that two gray mask, i can’t extract like the video, plz help me to fix that problem
This is the nature of masking. ZBrush always shows the polygons connected to masked points as being partially masked. It’s meant to help you see the effect of deformations. For example, if you mask points and then do an inflate deformation the “half-masked” polygons would be partially affected by the deformation because some of their points are frozen (and won’t move) while some are not (and will move). Because some points move and some don’t, the polygon itself is going to change shape.
The fewer polygons your model has, the more pronounced this effect will be.
When it comes to mesh extraction, ZBrush splits the difference. The actual edge of your extraction is going to be in the middle of the half-masked polygons.