https://www.cutoutandkeep.net/projects/photo-editing-in-mac-previewblack-and-white • Posted by michelle G.
its easy to try
its easy to try
find your picture
click to enlarge it
then go to tools--edit colours
go to saturation and pull all to the left this takes the colour out and turns to grey
then use the others like temputure and contrast to hone the image