SZ without halucinations VS. Delusional disorder

what’s the difference between a person with DD and with SZ which main symptom are delusions?

Found this on the subject

If it is main symptom, does that means that hallucinations happen sometimes, just not as often as delusions? I have been like that. My hallucinations have nearly always been rare and mild. Most of the time it is actually nothing more than the world not looking quite right, colors seem unreal in a weird way, things seem more sharply outlined, lighting looks wrong, etc.

well it’s not me, it’s my father so i dont know if he has them, i never asked him, i think i would notice, but delusions and paranoid thinking was as long as i can remember, anyway despite delusions he looks perfectly normal.