The Kiron and Vivitar 105 macros should be optically identical in all respects except possibly their coatings. I say optically identical, because the finish is different. I would assume they were build on the same assembly line, using the same internal baffling and diaphragm.
After offline dialogs with Fred, I'm less certain about the optical equivalence of the Vivitar Series 1 90/2.5 and its Tokina ATX 90/2.5 "twin." I say this not because the Vivitar uses a 58mm filter, the Tokina a 55; that's a "packaging" decision. Nor because the Vivitar includes a tripod ring while the Tokina, Fred informs me, does not. But rather, because they focus in different directions, suggesting--to me, at any rate--that they may have been made in different factories, and so all bets are off; perhaps they even cut from different glass. Steve Larson has written that the Vivitar has great color and bokeh, while a Minolta user was not impressed with the Tokina's bokeh. As for Vivitar's VMC (Vivitar Multi Coating), I have seen it deliver rich colors in my 28/1.9 but muted colors in my 135/2.3. I've read nothing about the Tokina's colors. However, these 90/2.5s (1:2, 1:1 with optional 1:1 3-3-element extender) were among the last great manual focus macros, coming on the scene around 1986. I would hope that that means their colors are richer. The color-rich 28/1.9 VMC came out in 1979, the color-mute 135/2.3 in 1977, suggesting that Vivitar found a way to apply protective coatings without stripping out the saturation. I can't speak for the Vivitar 105's color (1986), but my Kiron 105/2.8 PK's colors (1984) are on the muted side. (There goes a PDML sale.) Paul F. Stregevsky -------------------------------------------------------------------- mail2web - Check your email from the web at http://mail2web.com/ . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
