1:1 is not possible with the D500 close-up lens.
With extension tubes it is possible, but no guaranty how bad your IQ will turn out.
As a rule of thum, for 1:1 you need extension-tubes as long as the focal-length is of your lens. So you could do it with a 20mm extender. For 5:1 you would need around 100mm extender!
5xmagnification with decent IQ can only be done through lens reversal, but you need a special adapter. Don't know how much that is!
If you shoot with extenders you need to stop down the lens quite a bit te get an acceptable IQ, say f11, plus you lose 1 stop for 1:1 so your effectively shooting at f16. Taht has two consequences in comparison to a f2.8 dedicated macro lens:
1. You always have a dof that is much deeper than with a f2.8 lens
2. small subjects that move (e.g. through wind) will be very
hard to capture as your shutter speeds have to be comparably slow
If you do lens-reversal IQ will be equally bad from say 1:1 up to 5x magnification, as the lens is normally not corrected for the range 1:5-1:1.
So even in this case it's wisest to pick up a macro lens that is good for 1:1. Than you get sharp results when reversing it. Try to find a used fixed focus 1:1 marco lens if you're really into the world of the smallest things and have limited budget
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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