I'm a bit of a nerd and get picky when it comes to purchasing lenses in the way of serial numbers.  This is because 2 lenses with drastically different serial numbers give a unique look, to me.  Nikon is known to produce a run of a lens, stop production and begin another run beginning with a different serial number.  http://www.photosynt...n/serialno.html lists all the known serial numbers of Nikon lenses.  This post deals with the 135mm 2.0 DC.  I was in the market for a second copy recently and browsed many japanese sellers on ebay (japanese generally take excellent care of their gear in my experience).  After days of looking for the right condition/pricepoint, I noticed a lens with the serial# 500001.  This indicates the first lens of the 4th and final run of which 23,187 known copies were produced.  I know nothing of it's history, but I paid about 7 for it and it shipped from a used camera shop in Tokyo.  A bit of a holy grail for me.  Stunningly mint as though it had been mounted once to ensure proper function.  What are the chances.  Introduced in 1995, this is one of the oldest lenses to still have been in production and available on the Nikon website until just a few months ago.  Have you had any rare/special encounters with equipment?

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