Originally posted by lguckert79
i was asking cause i heard that sears had a bunch of lens made by a different company and stamped their logo on it and marketed it as theirs i was woundering abou the true company the manufactured the lens?
If you have a snap of it, someone might recognize it. Some Sears lenses were made by Ricoh, and pretty nice glass. Odds are that that one's pretty nice by today's standards, save perhaps for a lack of high-tech lens coatings (A good deep lens hood can help make up for that, though. )
For infinity focus, you'll definitely do well to invest in the 'Genuine Pentax' adapter. It's much less hassle/doesn't need special keys. The difference is that the kind that do not allow infinity focus have a flange that goes between the mount and the lens: the kind that do, just sit inside the camera's lens mount and don't have that flange. The genuine Pentax kind has a better latch to allow it to do this, basically.
Ash is right, though, if you have the lens in hand, you can explore for yourself how nice it is. (If you have doubts if it's you or the lens, just use solid camera support, and try different apertures, etc. I'll lay odds that's a pretty nice lens, though, at least if it's in good order.

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