Why use photoshop cs3 end to pull the map after the edge, there is still a small point

I am in the photo studio work, in the end to pull the photo after emergence to expand on the background to delete the photo to see enlarged beyond the four sides still have a small point, especially in the bigger picture when annoying, it is often small bars will be In another lens on the face, but also to re-use it to delete lasso circle again, with this photoshop 7.0 would be no problem, I would like to ask how to solve?

that is not clean because.and then you get points carefully.technology do not pass ^_^.
included in the constituency, the establishment of Layer Mask, with no transparency in the low brush Smear a little on the edge of what give it a try? Attention to the size of the strokes Oh.I usually do, I have heard some of the experts to explain.We hold the general map in photoshop, photoshop, but not in this area the best You can find a number of professional on-line deduction map software, in addition photoshop we can do it:
1.Ctrl + J
2.To find a color to go with other colors in different places, and to find The biggest difference in the channel:Copy ? curve (color) adjustment ? ? clear distinction with brush for constituencies ? delete.

? (generally small differences in the calculation and we can access computing, with particular Gray attention, you may be looking for, because I emergence of all gray) ? In general, smaller pixels, you use:layers – edge.

Try to remove the black side Or white side.