[jeffshaddix]

Hey guys,

I just got a KA mount Tokina AT-X 80-200/2.8 from the 'bay. The seller mentioned that it didn't focus at infinity until 85mm, but I don't think it ever really hits the proper infinity focus even out at 200mm. I know some of you guys are good with lens repair, so I thought I might try my luck here first. I've read in other threads that many of these old manual lenses came with three screws that can be loosened to adjust the focus, so that's what I'm looking for.

The first set of three screws I can see are up near the rotating front element. I'm guessing removing those would allow me to unscrew the front element - which I might do anyway to clear off some haze, but not yet.

There are of course the three screws holding the outer mount in place, and likewise the inner mount. Also not useful I'm guessing.

I also tried peeling up the rubber on the focus ring. I didn't see anything, but I only peeled up a little at the top and bottom.

If I loosen the tripod collar, I can rotate the collar to find three screws hidden underneath on the body - bingo?

What do you guys think? I want some people smarter than me to speak up before I start unscrewing things. See the pics below.

Cheers,
-Jeff

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[pentaxus]

Sometimes focus can be adjusted by loosening the set screws that the hold the front group in place and rotating the lens group to move it in and out to get proper focus. Re-tighten the set screws when done. On some zoom lenses you remove the rubber part of the focusing ring and you will see the scale half of the of the focusing ring taped to the front half. Remove the tape to adjust the focus and re-tape. Infinity focus is unlikely to be adjusted by anything in the back half.

[jeffshaddix]

Sometimes focus can be adjusted by loosening the set screws that the hold the front group in place and rotating the lens group to move it in and out to get proper focus. Re-tighten the set screws when done. On some zoom lenses you remove the rubber part of the focusing ring and you will see the scale half of the of the focusing ring taped to the front half. Remove the tape to adjust the focus and re-tape. Infinity focus is unlikely to be adjusted by anything in the back half.

Thanks for the response! So you think those screws near the top might do it? My concern there is it's probably for rotating the front element, not the whole group. I'll also look at peeling more of the rubber back - it concerns me a bit because it's got glue keeping it in place.

[jeffshaddix]

The ebayer gave me a full refund and told me to keep the lens, so I decided to just pay it forward to one of you guys who wants to try to fix it: https://www.pentaxforums.com/forums/24-photographic-equipment-sale/318975-sal...ng-charge.html