Yes, there are differences because the underlying theory is different – e.g. in critical ethnography you will design the research itself – and therefore questions and topics in your approach to the interview around issues of marginalization from the mainstream, or enablement of those marginalized within society in some way, or be concerned about redressing power imbalances – so your interview questions will be influenced by that, as will your curiosity as the researcher framing and designing the research. Ethnography tends to be curious about groups and communities (although defining community is extremely flexible) and that shapes the way the interviews are planned and take place. However there are commonalities too, but in a scholarly approach this difference v comonalities is something you want to consider very deeply – and also of course you will explore the contemporary literature from critical ethnography to explain why you made the research decisions you did, so that literature will bring a different perspective and flavor to your interviews, and later to your data treatment and analysis. The basic methods of ethnography (eg interviews) are the same across qualitative research approaches but they are refined and honed by the paradigm you work within.