Originally posted by royden TAMRON | Tamron Discontinued Products List
The above link lists Tammy discontinued lens. Mine is a 2002 model. Couldn't find a AO3S but there is a AO31 which is a 28-200..a 2010 model. Compare the info in the middle column and see if it matches yours. If your copy is a XR Di, you scored a major, super duper buy. That is a great shot that you posted. How do I use the macro on this lens? Google Viscaya museum, Miami, Fl. A beautiful place.
You asked about aVivitar with serial # 77xxxxxx. See link below. I have a 28-85/3.5-4.5....a nice lens and well built.
http://www.thomasgood.com/?p=1201
Mine says: Tamron AF Aspherical XR (IF) 28-200mm 1:3.8 - 5.6 MACRO. According to the Tamron Discontinued Products List, mine was discontinued in 2004. It is a model AO3S (The "S" I assume means "Silver.")
To shoot macro, all you do is zoom out to 200mm and focus as close as it will go. I usually just set the focus as close as I can get it, then move forward or backward until it's in focus.... unless I'm using a tripod. Mine, as you can see, is exceptionally sharp!
Thanks for the info on the Vivitar lens. I'll keep it, as well as the Tamron list in the folder I have set aside for such things.
Dewman
SW Idaho, USA