It is narrated from Sayyiduna Abdullah (may Allah be pleased with him) that he said: "Four things are part of coarseness: that a man hears the mu'adhdhin say the takbir and does not say the takbir himself, and hears him recite the tashahhud and does not recite the tashahhud himself; that he wipes the dust off his forehead while in prayer; and that he prays in open ground while there is no sutrah (screen) between himself and the qiblah."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 9469