Vivitar .43x aux lens

vivThis is an editorial. A few years ago I bought one of those cheap Vivitar .43x auxillary lenses. I wanted it to fit on my Tokina 28-70mm f/3.5 lens (which it did perfectly without an adapter). The reason I'm writing this is that I am finally very impressed with the versatility this lens gives me.
It comes in two parts. There is a 2.5x (focusing at about 4 cm) close-up lens at the back and the convex wide-angle converter at the front. You have to use both parts screwed together to get the wide angle conversion.
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http://2.bp.blogspot.com/-dymFcDx6-y...hcloseupSM.jpg
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http://4.bp.blogspot.com/-PSVPN7Bw5X...ithfullaux.jpg
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http://4.bp.blogspot.com/-N7JLSLbblf...crofullaux.jpg
It comes in two parts. There is a 2.5x (focusing at about 4 cm) close-up lens at the back and the convex wide-angle converter at the front. You have to use both parts screwed together to get the wide angle conversion.
.
http://2.bp.blogspot.com/-N9_m6WFqI2.../21mmequSM.jpg
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http://3.bp.blogspot.com/-cHrbA5Z_Ph.../45mmequiv.jpg


Vivitar .43x aux lens