If you want some really sharp and clear pictures, a DSLR camera is your best option. The cheapest available is good enough for this, your lens is the most important. For this picture I did use a 9 year old Canon EOS 50D, with a professional 100mm 2.8 L series macro lens.
This coin was in a PCGS slab and I was using natural daylight(I always do), a flash is not good for photographing coins in slabs (and proof coins in general) As a background I always use a regular A4 printing sheet, also with raw coins. my aperture was a little to high with f2.8 it's best to use f3.5 or 5.6.