I tend to use a primer under foundation if I wish to disguise deep pores or pitted acne scaring. The elf studio mineral infused primer is the primer I have found works best for this. You apply it once then use a stippling brush or a flat buffing brush to properly push it into the hole to essentially fill it in by stippling it in. I use the Real Techniques stippling brush. I then apply a thin full coverage foundation over this to avoid raised acne looking bigger such as the Revlon colourstay or l'oreal true match.