Harry0 Loc: Gardena, Cal

I gots one. The Sigma 70-210 UC lenses are supposed to be a POS, but this was a nice one.
A bit fuzzy the corners, still waay good enough for 5x7s. The ol APO is better, but inconvenient.
ANYway I went to use it this weekend. Sticky stuff on the barrel. Effort required to zoom, then the focus ring gets stiff. Rotate that a few times, it loosens up, then the zoom is stuck again.
Is this a new paperweight? Is it fixable? Easily fixable? Thanks in advance.

Longshadow Loc: Audubon, PA, United States

What's the temperature where it was stored?

What's an APO?

wingclui44 Loc: CT USA

It stands for'' apochromat', it means the lens is made with glass elements to correct the 'Chromatic aberration'.

rb61 Loc: Maple Grove, MN

Relevant thread?
https://www.pentaxforums.com/forums/58-troubleshooting-beginner-help/334697-sigma-70-210-rubber-problems.html

User ID

Sticky sigma ? Get thee to a urologist !

.

Harry0 Loc: Gardena, Cal

Stored at room temperature. Here in Socal, that's @ 65 to 90 degrees. Unused for @ a month.
Nope, it's not the rubber (bad farmer's daughter joke here somewhere). It's in surprisingly good shape, considering how long and how often I've handled it. I just now slipped it off, and there's no goo. The shaft there looks clean and nice, also. I might clean it and put a little Mother's love into it before I stick it back onto my thing. The APO shoots good, but it's a big ol heavy pumper, not really something I like pulling out in tight public areas. The UC is shorter, a lot lighter, with good girth. The sticky stuff is def on the lower shaft only, as if it was coming from under the focusing head. I'll try to clean it, see if it still seeps, but I don't want something that'll penetrate and give me that vaseline smear effect.

Harry0 Loc: Gardena, Cal

If I ever took half of my own advice I'd be somebody by now. -sigh-
Youtube- various tutorials, take apart, clean and fix, etc. Looks like an EX/PZ Sunday project.
In the meantime, looking thru the box of camera bits, I seem to have a spare 55-200 (non VR, why it was in there) modern kit lens. Almost new. Yeah, that'll work.
'Cause none of you can reach, I'll ask me wife to smack the back of my head, in your honor.
Thanks again!

jerryc41 Loc: Catskill Mts of NY

People always recommend avoiding any kind of lube, but if the lens is going to be put away forever, what's the harm in trying a little something?

https://richardhaw.com/tag/lens-grease/
https://www.dpreview.com/forums/post/19244517

Harry0 Loc: Gardena, Cal

That first suggestion should be on everyone's "Save as PDF" list. Thank you!
The second ... kinda amusing...
I've been playing with old folders for a loong while, now. With their construction, a basic rule of thumb was/is: clean is better than over lubed. A spray can of electronics cleaner has resurrected many Ikonta and Moskva shutters and timers.
But this thing had me stumped. It didn't build up gradually. I live in SoCal- the outside temp doesn't get below 40 degrees, or above 95. I'm married, the indoor temp stays between 60 and 80 degrees. BUT I'm going to look for a Round Tuit and a couple hours in a row and take it apart.