[Deleting pixel only under another pixel]

That was exactly what I was trying to do. Thanks so much. I just couldn't work out the correct sequence. Yes, basically I was just trying to cut the shape of one pixel layer out from another.

[Deleting pixel only under another pixel]

Hi,

 

I'm trying to subtract one pixel from another

i.e have a background pixel layer, place a pixel over it and then erase (or subtract?) *only* what is underneath the second pixel - leaving a hole in the background the same shape as the second pixel shape

I hope that makes sense...

I'm guessing that this is something to do with layers and masks, but can't for the life of me work it out.

 

Help!