Purchased by myself as a Photographic  resale item because it was a    Very Usable or collectible   ITEM: 1970's Samigon 300mm F:5 prime telephoto lens, made by Cosina in great clear Serviced Tested condition. 
                                  MECHANICALLY: USED- In very nice  shape, like it was never used, stored in a dry area of mt's of Pa.. TESTED- see photos good performer for older Prime lens
OPTICALLY:  outstanding condition for its  age. Unscratched optics and very clear! 
USE: ON all digital & SLR cameras Full frame or APS-C, SLR,DSLR,APS-C; all adapters available on eBay!
Info: Samigon Lenses Modern Photography, Jan. 1972, p. 102 Samigon Lens - Low Cost* Auto Diaphragm Prime Optics Samigon 35mm f/2.8 135mm f/2.8 300mm f/5 f/stops center edge center edge center edge 2.8 excellent acceptable acceptable acceptable 4 excellent acceptable very good acceptable very good excellent 5.6 excellent acceptable very good acceptable excellent very good 8 excellent acceptable very good acceptable excellent excellent 11 excellent acceptable very good good acceptable good 16 very good acceptable excellent good acceptable good 22 good acceptable very good acceptable acceptable acceptable Someone asked about Samigon lenses, which were popular in the 1970s as a low cost series of prime lenses (35mm $62, 135mm f/2.8 $69, and 300mm f/5 $145). The 35mm does surprisingly well in central resolution for a low cost optic, as does the 135mm. But most of us today would be more interested in the 300mm f/5, which is a good bit faster than the lower cost f/5.6 lenses often found, if slower than the prosumer 300mm f/4.5 and f/4 lenses out there. The odd part about the Samigon 300mm lens is how it is optimized for wide open use, at f/5 (max. opening) through f/8, but but falls off after that. This pattern is what you would want in a low cost 300mm, rather than the more usual improvements with stopping down to f/11 and f/16. You might also like the fact that the f/5 lens speed is still pretty fast, and usable wide open per the ratings, but less than the usual 300mm f/4 or f/4.5 pro-sumer lens speed. This parameter means the lens probably uses smaller filters, and is substantially lighter than its heavier cousins. My point here is that you can find some interesting candidates for further study by reviewing sample lens test data as we have above. Because this lens is not a big name brand, you can possibly get quite a bargain. Very often, the more expensive and better quality lenses in "no-name" brands or import labels can be good buys, as they are priced based on the more modest cost and reputation lenses in the line. You also have to test your lenses to ensure they work well, and learn how to use them optimally. J. Monghan
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