What I understand is both are coiled version of DNA along with histone but are termed different based on their degree of condensation. My question is when do we call it chromonema and when chromatin fiber? Do we consider 30nm fiber as chromatin and 10nm fiber as chromonema or something else?
10nm fibres are seen only by electron microscopy,while chromonema fibres refer to chromatin fibres visible by light microscopy. See this paper. 10nm or 30nm fibres are thus much, much smaller than chromenema fibres. There are likely several layers of organization (like 100nm and 200nm fibres) before you get all the way up to chromenema fibres.