Hello! Sorry, this has nothing to do with Pentax, I am just hoping that even though this is not the right forum, among so many experienced photographers there might be somebody knowledgeable on the issue.
I very seldom stop by pawn shops, but Today I saw a Tamron 70-210 f/2.8 (AF SP LD) with a Nikon mount at a local pawn shop. Since my brother is using D70, and he is looking for a reasonable tele-zoom, I thought I'd take a look. I was confused by this lens. Take a look here: http://www.komkon.org/~str/af-sp-70210f28marked.jpg 1. What is the function of the ring marked as "1"? I suspect it is for manual focusing. But is is strange - it can be rotated and moved along the lens (like the ring on the one-touch zooms), but I don't think it does focusing, as it is done by the ring just right of it. Also, in principle, focusing can be done (inconvenient, but possible) by rotating the front ring "2". So, how does one work with that ring? 2. What is the the purpose of the tab marked as "3" ? 3. At the shop, the lens was attached to a N80, and there was a piece of something like a foam-rubber near "4", as if it was a leftover of a foam-rubber ring between the lens and the body. Any idea why one might want to use it? Could that be an indication that something is wrong with the mount? The lens was not loose or anything. I haven't used Nikon lenses/cameras since 1997, so I forgot most peculiarities about N-mount (in)compatibility issues. Would this one be fully compatible with the D70? Thank you! Igor PS. The lens together with the N80 was listed at $399. PPS. Did Tamron ever make this lens with K-mount?
