50mm f1.8D and Extension Tubes on Parade
Prepared 2006-11-07 (169/11461) by Bill Claff

Just to give newcomers an idea as to the magnifications involved.
The attached image is a mosaic of eight shots using the 50mm f/1.8D AF Nikkor and the Kenko Automatic Extension Tube Set DG.
The target is a short metal ruler and an Intel Pentium keychain.
I was manually focusing on the ruler at closest focus with a macro rail.
Adjusted the images only to make contrast and brightness uniform.
Taken with a D200 at f/22 with ISO Auto on. And a tripod, of course.

extension	magnification	working distance	magnification
	at closest focus		at infinity focus
mm	x	mm	x
0	0.156	347	0.000
12	0.412	145	0.252
20	0.524	110	0.367
32	0.772	84	0.624
36	0.836	78	0.688
48	1.088	62	0.938
56	1.200	58	1.051
68	1.458	50	1.299

Magnification at infinity; note these are measured not computed.