DX vs FX close-focus distance

Can someone help me understand one thing please?

Currently shooting w/a D300 and a 50mm f/1.4G. Great lens, great bokeh. I get the equivalent of a 75mm focal range, and the lens focuses down to 18 inches, which is perfect.

Soon, move up to the D4, with a comparable focal range lens being the 85mm f/1.4G. This lens however, focuses closest at a whopping 3 feet.

Am I missing something, or just looking at it wrong?

I'd essentially love to retain my current focal range, and close focus distance (D300 + 50mm f/1.4G), but it seems like D4 + 85mm f/1.4G won't give me the same close-focus flexibility?

I kind of get lost in the DX vs FX crop vs focal range
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MICHAEL KORMOS PHOTOGRAPHY
http://www.michaelkormos.com