Magnetic lasso tool

[Karateman]

Hi Guys,

      When you are tracing an object with the magnetic lasso tool and you have gone round the profile, if you find that the contour hasnt quite been followed precisely by the flashing dotted line, is it possible to somehow pick up the edge of the dotted line that has gone astray from the contour and pull it back to the required edge, or do you have to step back and start again. Sometimes as you trace the profile your hand can slip and drag the tool away from the edge....very frustrating..

[c.pfaffenbichler]

One can use Layer Masks or Quick Mask Mode to make changes with Painting Tools for example. 

[Conrad_C · Accepted solution]

The Delete (Backspace) key is useful for this situation. As soon as you see a Magnetic Lasso segment go off track, press Delete (Backspace) and it will remove the last point so you can do it over.

It’s really best to do that as soon as you notice it stray, because you can’t redo a segment that was drawn several points ago. If that happens, you have to press Delete (Backspace) enough times to back up and reach the segment that went wrong, which ends up deleting all of the other points in between.

If you’ve already committed the Magnetic Lasso so that it’s an animated selection marquee (dotted line), where it’s no longer a path with points, the only way to edit it is to use standard selection editing techniques, such as using the Lasso tool in Add or Subtract mode as needed.

[Karateman]

Thanks,.....I tried what you say and yes you can delete points that stray from the  contour but not once the full profile has been completed, but at least you dont have to keep restarting the lasso'ing...

cheers

ps whats add and subtract mode if you dont mnd

[Conrad_C · Accepted solution]

The selection tools have Add/Subtract/Intersect modes. For example, suppose you drew a selection with the Lasso tool (or after committing the Magnetic Lasso tool) but there is a little area that sticks out and you want to trim it out of the selection. If you go up to the options bar and click the Subtract mode button, dragging the Lasso tool around the unwanted selection area will deselect just that area, leaving the rest selected. If you missed a spot, you can include it in the selection by switching the Lasso tool to Add mode and dragging over the missed area.

Experienced Photoshop users use the shortcuts so they don’t have to keep going up to the options bar. Holding down Shift puts a selection tool into Add mode, holding down Alt/Option puts it into Subtract mode. So you can work like this: Draw a selection with the Lasso tool, then...oops, I missed a spot, so I Shift-drag around it and it’s added. Oops, there’s an area that should not be part of the selection, so I Alt-drag/Option-drag around it and it’s trimmed off.

[c.pfaffenbichler]

Please read this (in particular the section titled "Supply pertinent information for more timely and effective answers”):
https://community.adobe.com/t5/using-the-community/community-how-to-guide-tips-amp-best-practices/td...