Most people start with a prime lens (as opposed to telephoto/zoom and wide lenses). A lens from f/2.0 to f/1.4 (lower is better) is considered fast . The 50mm f/1.8 prime lens is most common and should be available from Ebay and various camera stores used. If you're lucky you can buy a complete vintage film SLR camera with a good prime lens for cheap (<$50). There are f/1.2 and f/1.0 lenses but these are very old discontinued lenses that fall in the category of legend and luxury. When buying a lens its important to make sure there are no scratches or fuziness. If the lens needs cleaning or ever had fungus then its no good. As for the funny acronyms such as NAI, AI, AIS, etc. If it says F-mount somewhere and says manual it's good for our purposes. If the age indicated is 1977 or later you should be confident. The variations refer to how the mechanism control focus. We won't be using any of those functions. Unless you are a wiz at disassembling SLRs there's little chance of every using autofocus mechanism on these cameras. So go cheap and simple.
We have to mount the camera lens to our aparatus somehow. There are many options for getting hold of an F-mount.
- Cannibalize the F-mount from a Camera Body
- Cannibalize the F-mount from an Adapter (like a C-mount to F-mount adapter)
- Use a rear Nikon lens cap
Personally I like to use screws more than glue. Glue is tricky to adjust because I work slow. So I bought an old circa 1979 Canon EM. It had a 50mm f/1.8 Series E lens and the four screw F-mount. I may have to supplement the screws with glue later on but that only makes the job easier. Since my first prototype will be a spinner I don't need the fancy tube style adapter.
References to Lenses and Mounts
Another alternative for F-Mount:
Nikon part number 2717, K3 Female Nikon Bayonet F-Mount - for Custom Applications