MorphologicalPerimeter[//ImageAdjust,0.1]

DeleteSmallComponents[MorphologicalPerimeter[//ImageAdjust,0.1]]

MorphologicalComponents[//ImageAdjust,0.1]//Colorize

ClusteringComponents[,7]//Colorize

DeleteSmallComponents[MorphologicalPerimeter[//ImageAdjust,0.9]]

DeleteSmallComponents[MorphologicalComponents[//ImageAdjust,0.89]//Colorize]

ClusteringComponents[//ImageAdjust,5]//Colorize

SelectComponents[Binarize@(//ImageAdjust),#EnclosingComponentCount==0&]