The man in the photograph is certainly not a Rastafarian. The photo is probably more than a century old, and predates the Rasta movement by meany decades. It's also Noth African, and although cultural rastafarianism has become popular in parts of Africa, this is a relatively recent phenomenon. Rasta, of course, is Jamaicam in origin, and dates only to the 1930s.
The individual looks to me like a Moroccan Gnawa, and certainly his way of dress is consistent with that. The instrument might be a Gimbri. This is only a guess, but the photo is almost certainly 19th century North African .
Calling any old-time highly ornamented African elder a rastaman is the kind of cultural ignorance that reduces the magnificent diversity and incomparable scope of African traditions to a meaningless stereotype.