What size sensor for Macro

What size sensor (full, 1.3, 1.6) would be best for Macro photograph using the canon 100mm macro. Would a full frame be best.

Dai

Assuming the viewfinder is bright enough and big enough for YOUR eyes to manually focus, and assuming no diffraction limited high f/stops above, say above f/16, then the higher pixel density of a 1.6 field of view crop camera puts more pixels on a macro subject compared to a full frame. You get more depth of field at an f/stop assuming the camera position is moved back. Camera position closer, and you get an apparent (fake) magnification advantage (just more pixels in the frame).

The same benefit field of view crop sensor cameras offer telephoto users, they offer to macro users. It is really at wide angle that FOVC sensor cameras are truly disadvantaged.

Trouble is things are never just equal... are they? A big, bright full 35mm frame viewfinder for easier manual focus counts for a lot, as does ability to use higher f/stops.

Frankly, as long as YOU can see to focus, you can take great macro shots with any of the cameras. 1.6, 1.3, 35mm, blah, blah, blah. My favorite compromise combo is the APS-H 1.3 1-D MkII with a 90mm TS-E Tilt shift lens, a 1.4 teleconverter, and 25 or 12mm extension tube. This is bright enough to focus, more dense pixels than full frame, and the tilt shift means sharp subjects at f/5.6, and I mean ALL the subject. Have fun.
Jack