Old beast lens info (300/5.6 prime)

[Cory Papenfuss]

	Hey all... I recently got an old Sears-branded 300mm f/5.6 
screwmount telephoto.  From the looks of it, it seems to be identical to 
a vivitar on ebay like this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=707&item=7502072857&rd=1&ssPageName=WDVW

	From the S/N, its alegedly Tokina-built if it's a Vivitar model. 
Looks a lot like the second from the right in the back of this pile: 
http://www.vermontel.net/~wsalati/CasualCollector/t4_for_two.htm

	Does anyone know of this sort of beast?  I know a lot of the 
Vivitars are cult classic enough to have lots of info on them, but 
off-off-brand (like the Sears) are tough to find info on.  It seems to 
take pretty good shots on my *ist-DS, with a bit of CA on the edges.  It 
doesn't say multicoated on it anywhere, but is it possible it is, anyway?

	Just looking to know if there are any thoughts on an old clunker 
like this.

Thanks,
-Cory
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* Cory Papenfuss                                                        *
* Electrical Engineering candidate Ph.D. graduate student               *
* Virginia Polytechnic Institute and State University                   *
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