from my Rebel..
iphone5...
what lens you use on the rebel... and uncropped?
and yeah... my kit is pretty pricey, but i'm pretty sure the body makes minimal difference in this scenario... really, any dslr could similar, if not better. i slapped on the only macro lens i bought.. which i found to be 100% useless... well, until this thread popped up! lol... a 35mm macro isn't all that useful due to working distance. (Obviously, i don't shoot macro very much).
But anyways... my point really was that if you want to print large size, you need large files... so cropping pics out of the camera is a counter intuitive way of "zooming." For uses online, its fine... but large prints is a completely different ball game.
Also... it seems that most peoples pics of coils is useful and such, but not quite what i'd consider macro...
But to the OP... how close of a shot you looking to take of your coils? hell... if i was spending my time building some of those crazy intricate coils, i'd probably want to be all up in there so all those details can be seen up front and center... but that's me. and obviously from my pics, i don't take too much time building my coils... lol.