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This is the one I have. The 35mm is a very short lens, only 1.7" deep by 2.5" wide, with a 52mm filter size. Minimum focus is 9.8" and magnification is only .24
The 40mm micro is 2.7x2.4 with 6.4" minimum focus and 1:1 at that distance. Not much working distance. 1:1 would be right on top of the port, but it should still give you decent macro, which the 35mm won't.
I've also used the 35mm in the NX Dome port, where it works, but not as well. With it's shorter focal length, the 40mm might work in a dome as a wide angle close focus, but being a macro you would not likely get a sharp background, but rather a bokeh.