I know that there are many Nikon lenses, but only a select few will work right with the D40, the Pentax will use almost any lens produces for a Pentax. I thought I saw somewhere that the glass in the Pentax is up there with the glass used in the Leica's. A Leica would be my first choice for a camera, but way out of my price range...

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2018 Subaru Crosstrek (Mine)
2019 Subaru Outback (Wife's)
1979 300CD (sold)